diff options
Diffstat (limited to 'module/zfs')
-rw-r--r-- | module/zfs/arc.c | 166 | ||||
-rw-r--r-- | module/zfs/dbuf.c | 68 | ||||
-rw-r--r-- | module/zfs/dmu.c | 37 | ||||
-rw-r--r-- | module/zfs/dmu_objset.c | 2 | ||||
-rw-r--r-- | module/zfs/dmu_tx.c | 207 | ||||
-rw-r--r-- | module/zfs/dmu_zfetch.c | 6 | ||||
-rw-r--r-- | module/zfs/dnode.c | 17 | ||||
-rw-r--r-- | module/zfs/dsl_dir.c | 50 | ||||
-rw-r--r-- | module/zfs/dsl_pool.c | 360 | ||||
-rw-r--r-- | module/zfs/dsl_scan.c | 5 | ||||
-rw-r--r-- | module/zfs/spa.c | 92 | ||||
-rw-r--r-- | module/zfs/spa_misc.c | 46 | ||||
-rw-r--r-- | module/zfs/txg.c | 33 | ||||
-rw-r--r-- | module/zfs/vdev.c | 4 | ||||
-rw-r--r-- | module/zfs/vdev_cache.c | 2 | ||||
-rw-r--r-- | module/zfs/vdev_mirror.c | 4 | ||||
-rw-r--r-- | module/zfs/vdev_queue.c | 734 | ||||
-rw-r--r-- | module/zfs/vdev_raidz.c | 2 | ||||
-rw-r--r-- | module/zfs/zfs_fm.c | 2 | ||||
-rw-r--r-- | module/zfs/zfs_vnops.c | 37 | ||||
-rw-r--r-- | module/zfs/zil.c | 2 | ||||
-rw-r--r-- | module/zfs/zio.c | 83 |
22 files changed, 1307 insertions, 652 deletions
diff --git a/module/zfs/arc.c b/module/zfs/arc.c index 6aa7d37c7..9cdb52011 100644 --- a/module/zfs/arc.c +++ b/module/zfs/arc.c @@ -134,6 +134,7 @@ #include <sys/arc.h> #include <sys/vdev.h> #include <sys/vdev_impl.h> +#include <sys/dsl_pool.h> #ifdef _KERNEL #include <sys/vmsystm.h> #include <vm/anon.h> @@ -162,6 +163,12 @@ typedef enum arc_reclaim_strategy { ARC_RECLAIM_CONS /* Conservative reclaim strategy */ } arc_reclaim_strategy_t; +/* + * The number of iterations through arc_evict_*() before we + * drop & reacquire the lock. + */ +int arc_evict_iterations = 100; + /* number of seconds before growing cache again */ int zfs_arc_grow_retry = 5; @@ -183,6 +190,11 @@ int zfs_arc_memory_throttle_disable = 1; /* disable duplicate buffer eviction */ int zfs_disable_dup_eviction = 0; +/* + * If this percent of memory is free, don't throttle. + */ +int arc_lotsfree_percent = 10; + static int arc_dead; /* expiration time for arc_no_grow */ @@ -519,6 +531,7 @@ typedef struct arc_write_callback arc_write_callback_t; struct arc_write_callback { void *awcb_private; arc_done_func_t *awcb_ready; + arc_done_func_t *awcb_physdone; arc_done_func_t *awcb_done; arc_buf_t *awcb_buf; }; @@ -1253,7 +1266,7 @@ arc_change_state(arc_state_t *new_state, arc_buf_hdr_t *ab, kmutex_t *hash_lock) uint64_t from_delta, to_delta; ASSERT(MUTEX_HELD(hash_lock)); - ASSERT(new_state != old_state); + ASSERT3P(new_state, !=, old_state); ASSERT(refcnt == 0 || ab->b_datacnt > 0); ASSERT(ab->b_datacnt == 0 || !GHOST_STATE(new_state)); ASSERT(ab->b_datacnt <= 1 || old_state != arc_anon); @@ -1859,6 +1872,8 @@ arc_evict(arc_state_t *state, uint64_t spa, int64_t bytes, boolean_t recycle, kmutex_t *hash_lock; boolean_t have_lock; void *stolen = NULL; + arc_buf_hdr_t marker = {{{ 0 }}}; + int count = 0; ASSERT(state == arc_mru || state == arc_mfu); @@ -1882,6 +1897,33 @@ arc_evict(arc_state_t *state, uint64_t spa, int64_t bytes, boolean_t recycle, if (recycle && ab->b_size != bytes && ab_prev && ab_prev->b_size == bytes) continue; + + /* ignore markers */ + if (ab->b_spa == 0) + continue; + + /* + * It may take a long time to evict all the bufs requested. + * To avoid blocking all arc activity, periodically drop + * the arcs_mtx and give other threads a chance to run + * before reacquiring the lock. + * + * If we are looking for a buffer to recycle, we are in + * the hot code path, so don't sleep. + */ + if (!recycle && count++ > arc_evict_iterations) { + list_insert_after(list, ab, &marker); + mutex_exit(&evicted_state->arcs_mtx); + mutex_exit(&state->arcs_mtx); + kpreempt(KPREEMPT_SYNC); + mutex_enter(&state->arcs_mtx); + mutex_enter(&evicted_state->arcs_mtx); + ab_prev = list_prev(list, &marker); + list_remove(list, &marker); + count = 0; + continue; + } + hash_lock = HDR_LOCK(ab); have_lock = MUTEX_HELD(hash_lock); if (have_lock || mutex_tryenter(hash_lock)) { @@ -1963,27 +2005,11 @@ arc_evict(arc_state_t *state, uint64_t spa, int64_t bytes, boolean_t recycle, ARCSTAT_INCR(arcstat_mutex_miss, missed); /* - * We have just evicted some data into the ghost state, make - * sure we also adjust the ghost state size if necessary. + * Note: we have just evicted some data into the ghost state, + * potentially putting the ghost size over the desired size. Rather + * that evicting from the ghost list in this hot code path, leave + * this chore to the arc_reclaim_thread(). */ - if (arc_no_grow && - arc_mru_ghost->arcs_size + arc_mfu_ghost->arcs_size > arc_c) { - int64_t mru_over = arc_anon->arcs_size + arc_mru->arcs_size + - arc_mru_ghost->arcs_size - arc_c; - - if (mru_over > 0 && arc_mru_ghost->arcs_lsize[type] > 0) { - int64_t todelete = - MIN(arc_mru_ghost->arcs_lsize[type], mru_over); - arc_evict_ghost(arc_mru_ghost, 0, todelete, - ARC_BUFC_DATA); - } else if (arc_mfu_ghost->arcs_lsize[type] > 0) { - int64_t todelete = MIN(arc_mfu_ghost->arcs_lsize[type], - arc_mru_ghost->arcs_size + - arc_mfu_ghost->arcs_size - arc_c); - arc_evict_ghost(arc_mfu_ghost, 0, todelete, - ARC_BUFC_DATA); - } - } return (stolen); } @@ -2002,6 +2028,7 @@ arc_evict_ghost(arc_state_t *state, uint64_t spa, int64_t bytes, kmutex_t *hash_lock; uint64_t bytes_deleted = 0; uint64_t bufs_skipped = 0; + int count = 0; ASSERT(GHOST_STATE(state)); bzero(&marker, sizeof(marker)); @@ -2009,6 +2036,8 @@ top: mutex_enter(&state->arcs_mtx); for (ab = list_tail(list); ab; ab = ab_prev) { ab_prev = list_prev(list, ab); + if (ab->b_type > ARC_BUFC_NUMTYPES) + panic("invalid ab=%p", (void *)ab); if (spa && ab->b_spa != spa) continue; @@ -2020,6 +2049,23 @@ top: /* caller may be trying to modify this buffer, skip it */ if (MUTEX_HELD(hash_lock)) continue; + + /* + * It may take a long time to evict all the bufs requested. + * To avoid blocking all arc activity, periodically drop + * the arcs_mtx and give other threads a chance to run + * before reacquiring the lock. + */ + if (count++ > arc_evict_iterations) { + list_insert_after(list, ab, &marker); + mutex_exit(&state->arcs_mtx); + kpreempt(KPREEMPT_SYNC); + mutex_enter(&state->arcs_mtx); + ab_prev = list_prev(list, &marker); + list_remove(list, &marker); + count = 0; + continue; + } if (mutex_tryenter(hash_lock)) { ASSERT(!HDR_IO_IN_PROGRESS(ab)); ASSERT(ab->b_buf == NULL); @@ -2055,8 +2101,9 @@ top: mutex_enter(&state->arcs_mtx); ab_prev = list_prev(list, &marker); list_remove(list, &marker); - } else + } else { bufs_skipped += 1; + } } mutex_exit(&state->arcs_mtx); @@ -3050,7 +3097,7 @@ arc_read_done(zio_t *zio) */ int arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, arc_done_func_t *done, - void *private, int priority, int zio_flags, uint32_t *arc_flags, + void *private, zio_priority_t priority, int zio_flags, uint32_t *arc_flags, const zbookmark_t *zb) { arc_buf_hdr_t *hdr; @@ -3702,6 +3749,18 @@ arc_write_ready(zio_t *zio) hdr->b_flags |= ARC_IO_IN_PROGRESS; } +/* + * The SPA calls this callback for each physical write that happens on behalf + * of a logical write. See the comment in dbuf_write_physdone() for details. + */ +static void +arc_write_physdone(zio_t *zio) +{ + arc_write_callback_t *cb = zio->io_private; + if (cb->awcb_physdone != NULL) + cb->awcb_physdone(zio, cb->awcb_buf, cb->awcb_private); +} + static void arc_write_done(zio_t *zio) { @@ -3782,8 +3841,9 @@ arc_write_done(zio_t *zio) zio_t * arc_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, boolean_t l2arc_compress, - const zio_prop_t *zp, arc_done_func_t *ready, arc_done_func_t *done, - void *private, int priority, int zio_flags, const zbookmark_t *zb) + const zio_prop_t *zp, arc_done_func_t *ready, arc_done_func_t *physdone, + arc_done_func_t *done, void *private, zio_priority_t priority, + int zio_flags, const zbookmark_t *zb) { arc_buf_hdr_t *hdr = buf->b_hdr; arc_write_callback_t *callback; @@ -3800,39 +3860,30 @@ arc_write(zio_t *pio, spa_t *spa, uint64_t txg, hdr->b_flags |= ARC_L2COMPRESS; callback = kmem_zalloc(sizeof (arc_write_callback_t), KM_PUSHPAGE); callback->awcb_ready = ready; + callback->awcb_physdone = physdone; callback->awcb_done = done; callback->awcb_private = private; callback->awcb_buf = buf; zio = zio_write(pio, spa, txg, bp, buf->b_data, hdr->b_size, zp, - arc_write_ready, arc_write_done, callback, priority, zio_flags, zb); + arc_write_ready, arc_write_physdone, arc_write_done, callback, + priority, zio_flags, zb); return (zio); } static int -arc_memory_throttle(uint64_t reserve, uint64_t inflight_data, uint64_t txg) +arc_memory_throttle(uint64_t reserve, uint64_t txg) { #ifdef _KERNEL - uint64_t available_memory; - if (zfs_arc_memory_throttle_disable) return (0); - /* Easily reclaimable memory (free + inactive + arc-evictable) */ - available_memory = ptob(spl_kmem_availrmem()) + arc_evictable_memory(); - - if (available_memory <= zfs_write_limit_max) { + if (freemem <= physmem * arc_lotsfree_percent / 100) { ARCSTAT_INCR(arcstat_memory_throttle_count, 1); DMU_TX_STAT_BUMP(dmu_tx_memory_reclaim); return (SET_ERROR(EAGAIN)); } - - if (inflight_data > available_memory / 4) { - ARCSTAT_INCR(arcstat_memory_throttle_count, 1); - DMU_TX_STAT_BUMP(dmu_tx_memory_inflight); - return (ERESTART); - } #endif return (0); } @@ -3850,15 +3901,6 @@ arc_tempreserve_space(uint64_t reserve, uint64_t txg) int error; uint64_t anon_size; -#ifdef ZFS_DEBUG - /* - * Once in a while, fail for no reason. Everything should cope. - */ - if (spa_get_random(10000) == 0) { - dprintf("forcing random failure\n"); - return (ERESTART); - } -#endif if (reserve > arc_c/4 && !arc_no_grow) arc_c = MIN(arc_c_max, reserve * 4); if (reserve > arc_c) { @@ -3878,7 +3920,8 @@ arc_tempreserve_space(uint64_t reserve, uint64_t txg) * in order to compress/encrypt/etc the data. We therefore need to * make sure that there is sufficient available memory for this. */ - if ((error = arc_memory_throttle(reserve, anon_size, txg))) + error = arc_memory_throttle(reserve, txg); + if (error != 0) return (error); /* @@ -4075,11 +4118,24 @@ arc_init(void) arc_dead = FALSE; arc_warm = B_FALSE; - if (zfs_write_limit_max == 0) - zfs_write_limit_max = ptob(physmem) >> zfs_write_limit_shift; - else - zfs_write_limit_shift = 0; - mutex_init(&zfs_write_limit_lock, NULL, MUTEX_DEFAULT, NULL); + /* + * Calculate maximum amount of dirty data per pool. + * + * If it has been set by a module parameter, take that. + * Otherwise, use a percentage of physical memory defined by + * zfs_dirty_data_max_percent (default 10%) with a cap at + * zfs_dirty_data_max_max (default 25% of physical memory). + */ + if (zfs_dirty_data_max_max == 0) + zfs_dirty_data_max_max = physmem * PAGESIZE * + zfs_dirty_data_max_max_percent / 100; + + if (zfs_dirty_data_max == 0) { + zfs_dirty_data_max = physmem * PAGESIZE * + zfs_dirty_data_max_percent / 100; + zfs_dirty_data_max = MIN(zfs_dirty_data_max, + zfs_dirty_data_max_max); + } } void @@ -4137,8 +4193,6 @@ arc_fini(void) mutex_destroy(&arc_mfu_ghost->arcs_mtx); mutex_destroy(&arc_l2c_only->arcs_mtx); - mutex_destroy(&zfs_write_limit_lock); - buf_fini(); ASSERT(arc_loaned_bytes == 0); diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c index 9ad3d1d30..01352a91c 100644 --- a/module/zfs/dbuf.c +++ b/module/zfs/dbuf.c @@ -891,7 +891,7 @@ dbuf_free_range(dnode_t *dn, uint64_t start, uint64_t end, dmu_tx_t *tx) atomic_inc_64(&zfs_free_range_recv_miss); } - for (db = list_head(&dn->dn_dbufs); db; db = db_next) { + for (db = list_head(&dn->dn_dbufs); db != NULL; db = db_next) { db_next = list_next(&dn->dn_dbufs, db); ASSERT(db->db_blkid != DMU_BONUS_BLKID); @@ -1238,6 +1238,8 @@ dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t *tx) sizeof (dbuf_dirty_record_t), offsetof(dbuf_dirty_record_t, dr_dirty_node)); } + if (db->db_blkid != DMU_BONUS_BLKID && os->os_dsl_dataset != NULL) + dr->dr_accounted = db->db.db_size; dr->dr_dbuf = db; dr->dr_txg = tx->tx_txg; dr->dr_next = *drp; @@ -1321,7 +1323,10 @@ dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t *tx) dbuf_rele(parent, FTAG); mutex_enter(&db->db_mtx); - /* possible race with dbuf_undirty() */ + /* + * Since we've dropped the mutex, it's possible that + * dbuf_undirty() might have changed this out from under us. + */ if (db->db_last_dirty == dr || dn->dn_object == DMU_META_DNODE_OBJECT) { mutex_enter(&di->dt.di.dr_mtx); @@ -1391,7 +1396,11 @@ dbuf_undirty(dmu_buf_impl_t *db, dmu_tx_t *tx) ASSERT(db->db.db_size != 0); - /* XXX would be nice to fix up dn_towrite_space[] */ + /* + * Any space we accounted for in dp_dirty_* will be cleaned up by + * dsl_pool_sync(). This is relatively rare so the discrepancy + * is not a big deal. + */ *drp = dr->dr_next; @@ -1571,7 +1580,7 @@ dbuf_assign_arcbuf(dmu_buf_impl_t *db, arc_buf_t *buf, dmu_tx_t *tx) /* * "Clear" the contents of this dbuf. This will mark the dbuf - * EVICTING and clear *most* of its references. Unfortunetely, + * EVICTING and clear *most* of its references. Unfortunately, * when we are not holding the dn_dbufs_mtx, we can't clear the * entry in the dn_dbufs list. We have to wait until dbuf_destroy() * in this case. For callers from the DMU we will usually see: @@ -1768,7 +1777,7 @@ dbuf_create(dnode_t *dn, uint8_t level, uint64_t blkid, db->db.db_offset = 0; } else { int blocksize = - db->db_level ? 1<<dn->dn_indblkshift : dn->dn_datablksz; + db->db_level ? 1 << dn->dn_indblkshift : dn->dn_datablksz; db->db.db_size = blocksize; db->db.db_offset = db->db_blkid * blocksize; } @@ -1877,7 +1886,7 @@ dbuf_destroy(dmu_buf_impl_t *db) } void -dbuf_prefetch(dnode_t *dn, uint64_t blkid) +dbuf_prefetch(dnode_t *dn, uint64_t blkid, zio_priority_t prio) { dmu_buf_impl_t *db = NULL; blkptr_t *bp = NULL; @@ -1901,8 +1910,6 @@ dbuf_prefetch(dnode_t *dn, uint64_t blkid) if (dbuf_findbp(dn, 0, blkid, TRUE, &db, &bp, NULL) == 0) { if (bp && !BP_IS_HOLE(bp)) { - int priority = dn->dn_type == DMU_OT_DDT_ZAP ? - ZIO_PRIORITY_DDT_PREFETCH : ZIO_PRIORITY_ASYNC_READ; dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset; uint32_t aflags = ARC_NOWAIT | ARC_PREFETCH; zbookmark_t zb; @@ -1911,7 +1918,7 @@ dbuf_prefetch(dnode_t *dn, uint64_t blkid) dn->dn_object, 0, blkid); (void) arc_read(NULL, dn->dn_objset->os_spa, - bp, NULL, NULL, priority, + bp, NULL, NULL, prio, ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, &aflags, &zb); } @@ -2647,6 +2654,38 @@ dbuf_write_ready(zio_t *zio, arc_buf_t *buf, void *vdb) mutex_exit(&db->db_mtx); } +/* + * The SPA will call this callback several times for each zio - once + * for every physical child i/o (zio->io_phys_children times). This + * allows the DMU to monitor the progress of each logical i/o. For example, + * there may be 2 copies of an indirect block, or many fragments of a RAID-Z + * block. There may be a long delay before all copies/fragments are completed, + * so this callback allows us to retire dirty space gradually, as the physical + * i/os complete. + */ +/* ARGSUSED */ +static void +dbuf_write_physdone(zio_t *zio, arc_buf_t *buf, void *arg) +{ + dmu_buf_impl_t *db = arg; + objset_t *os = db->db_objset; + dsl_pool_t *dp = dmu_objset_pool(os); + dbuf_dirty_record_t *dr; + int delta = 0; + + dr = db->db_data_pending; + ASSERT3U(dr->dr_txg, ==, zio->io_txg); + + /* + * The callback will be called io_phys_children times. Retire one + * portion of our dirty space each time we are called. Any rounding + * error will be cleaned up by dsl_pool_sync()'s call to + * dsl_pool_undirty_space(). + */ + delta = dr->dr_accounted / zio->io_phys_children; + dsl_pool_undirty_space(dp, delta, zio->io_txg); +} + /* ARGSUSED */ static void dbuf_write_done(zio_t *zio, arc_buf_t *buf, void *vdb) @@ -2741,6 +2780,7 @@ dbuf_write_done(zio_t *zio, arc_buf_t *buf, void *vdb) ASSERT(db->db_dirtycnt > 0); db->db_dirtycnt -= 1; db->db_data_pending = NULL; + dbuf_rele_and_unlock(db, (void *)(uintptr_t)txg); } @@ -2859,8 +2899,8 @@ dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx) ASSERT(db->db_state != DB_NOFILL); dr->dr_zio = zio_write(zio, os->os_spa, txg, db->db_blkptr, data->b_data, arc_buf_size(data), &zp, - dbuf_write_override_ready, dbuf_write_override_done, dr, - ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb); + dbuf_write_override_ready, NULL, dbuf_write_override_done, + dr, ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb); mutex_enter(&db->db_mtx); dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN; zio_write_override(dr->dr_zio, &dr->dt.dl.dr_overridden_by, @@ -2870,7 +2910,7 @@ dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx) ASSERT(zp.zp_checksum == ZIO_CHECKSUM_OFF); dr->dr_zio = zio_write(zio, os->os_spa, txg, db->db_blkptr, NULL, db->db.db_size, &zp, - dbuf_write_nofill_ready, dbuf_write_nofill_done, db, + dbuf_write_nofill_ready, NULL, dbuf_write_nofill_done, db, ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED | ZIO_FLAG_NODATA, &zb); } else { @@ -2878,8 +2918,8 @@ dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx) dr->dr_zio = arc_write(zio, os->os_spa, txg, db->db_blkptr, data, DBUF_IS_L2CACHEABLE(db), DBUF_IS_L2COMPRESSIBLE(db), &zp, dbuf_write_ready, - dbuf_write_done, db, ZIO_PRIORITY_ASYNC_WRITE, - ZIO_FLAG_MUSTSUCCEED, &zb); + dbuf_write_physdone, dbuf_write_done, db, + ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb); } } diff --git a/module/zfs/dmu.c b/module/zfs/dmu.c index 72fce35c5..ade13b9f0 100644 --- a/module/zfs/dmu.c +++ b/module/zfs/dmu.c @@ -370,13 +370,11 @@ static int dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags) { - dsl_pool_t *dp = NULL; dmu_buf_t **dbp; uint64_t blkid, nblks, i; uint32_t dbuf_flags; int err; zio_t *zio; - hrtime_t start = 0; ASSERT(length <= DMU_MAX_ACCESS); @@ -404,9 +402,6 @@ dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length, } dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_PUSHPAGE | KM_NODEBUG); - if (dn->dn_objset->os_dsl_dataset) - dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool; - start = gethrtime(); zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL); blkid = dbuf_whichblock(dn, offset); for (i = 0; i < nblks; i++) { @@ -427,9 +422,6 @@ dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length, /* wait for async i/o */ err = zio_wait(zio); - /* track read overhead when we are in sync context */ - if (dp && dsl_pool_sync_context(dp)) - dp->dp_read_overhead += gethrtime() - start; if (err) { dmu_buf_rele_array(dbp, nblks, tag); return (err); @@ -511,12 +503,22 @@ dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag) kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); } +/* + * Issue prefetch i/os for the given blocks. + * + * Note: The assumption is that we *know* these blocks will be needed + * almost immediately. Therefore, the prefetch i/os will be issued at + * ZIO_PRIORITY_SYNC_READ + * + * Note: indirect blocks and other metadata will be read synchronously, + * causing this function to block if they are not already cached. + */ void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) { dnode_t *dn; uint64_t blkid; - int nblks, i, err; + int nblks, err; if (zfs_prefetch_disable) return; @@ -529,7 +531,7 @@ dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) rw_enter(&dn->dn_struct_rwlock, RW_READER); blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t)); - dbuf_prefetch(dn, blkid); + dbuf_prefetch(dn, blkid, ZIO_PRIORITY_SYNC_READ); rw_exit(&dn->dn_struct_rwlock); return; } @@ -546,16 +548,18 @@ dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len) rw_enter(&dn->dn_struct_rwlock, RW_READER); if (dn->dn_datablkshift) { int blkshift = dn->dn_datablkshift; - nblks = (P2ROUNDUP(offset+len, 1<<blkshift) - - P2ALIGN(offset, 1<<blkshift)) >> blkshift; + nblks = (P2ROUNDUP(offset + len, 1 << blkshift) - + P2ALIGN(offset, 1 << blkshift)) >> blkshift; } else { nblks = (offset < dn->dn_datablksz); } if (nblks != 0) { + int i; + blkid = dbuf_whichblock(dn, offset); for (i = 0; i < nblks; i++) - dbuf_prefetch(dn, blkid+i); + dbuf_prefetch(dn, blkid + i, ZIO_PRIORITY_SYNC_READ); } rw_exit(&dn->dn_struct_rwlock); @@ -1559,7 +1563,7 @@ dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd, zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp, zgd->zgd_db->db_data, zgd->zgd_db->db_size, zp, - dmu_sync_late_arrival_ready, dmu_sync_late_arrival_done, dsa, + dmu_sync_late_arrival_ready, NULL, dmu_sync_late_arrival_done, dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL | ZIO_FLAG_FASTWRITE, zb)); return (0); @@ -1699,8 +1703,9 @@ dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd) zio_nowait(arc_write(pio, os->os_spa, txg, bp, dr->dt.dl.dr_data, DBUF_IS_L2CACHEABLE(db), - DBUF_IS_L2COMPRESSIBLE(db), &zp, dmu_sync_ready, dmu_sync_done, - dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL | ZIO_FLAG_FASTWRITE, &zb)); + DBUF_IS_L2COMPRESSIBLE(db), &zp, dmu_sync_ready, + NULL, dmu_sync_done, dsa, ZIO_PRIORITY_SYNC_WRITE, + ZIO_FLAG_CANFAIL, &zb)); return (0); } diff --git a/module/zfs/dmu_objset.c b/module/zfs/dmu_objset.c index 6a3b5f05e..07e00c307 100644 --- a/module/zfs/dmu_objset.c +++ b/module/zfs/dmu_objset.c @@ -1032,7 +1032,7 @@ dmu_objset_sync(objset_t *os, zio_t *pio, dmu_tx_t *tx) zio = arc_write(pio, os->os_spa, tx->tx_txg, os->os_rootbp, os->os_phys_buf, DMU_OS_IS_L2CACHEABLE(os), DMU_OS_IS_L2COMPRESSIBLE(os), &zp, dmu_objset_write_ready, - dmu_objset_write_done, os, ZIO_PRIORITY_ASYNC_WRITE, + NULL, dmu_objset_write_done, os, ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb); /* diff --git a/module/zfs/dmu_tx.c b/module/zfs/dmu_tx.c index ece6b14b3..47cb86b08 100644 --- a/module/zfs/dmu_tx.c +++ b/module/zfs/dmu_tx.c @@ -53,7 +53,8 @@ dmu_tx_stats_t dmu_tx_stats = { { "dmu_tx_memory_reclaim", KSTAT_DATA_UINT64 }, { "dmu_tx_memory_inflight", KSTAT_DATA_UINT64 }, { "dmu_tx_dirty_throttle", KSTAT_DATA_UINT64 }, - { "dmu_tx_write_limit", KSTAT_DATA_UINT64 }, + { "dmu_tx_dirty_delay", KSTAT_DATA_UINT64 }, + { "dmu_tx_dirty_over_max", KSTAT_DATA_UINT64 }, { "dmu_tx_quota", KSTAT_DATA_UINT64 }, }; @@ -70,6 +71,7 @@ dmu_tx_create_dd(dsl_dir_t *dd) offsetof(dmu_tx_hold_t, txh_node)); list_create(&tx->tx_callbacks, sizeof (dmu_tx_callback_t), offsetof(dmu_tx_callback_t, dcb_node)); + tx->tx_start = gethrtime(); #ifdef DEBUG_DMU_TX refcount_create(&tx->tx_space_written); refcount_create(&tx->tx_space_freed); @@ -614,6 +616,7 @@ dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off, uint64_t len) if (txh == NULL) return; dn = txh->txh_dnode; + dmu_tx_count_dnode(txh); if (off >= (dn->dn_maxblkid+1) * dn->dn_datablksz) return; @@ -931,6 +934,142 @@ dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db) } #endif +/* + * If we can't do 10 iops, something is wrong. Let us go ahead + * and hit zfs_dirty_data_max. + */ +hrtime_t zfs_delay_max_ns = 100 * MICROSEC; /* 100 milliseconds */ +int zfs_delay_resolution_ns = 100 * 1000; /* 100 microseconds */ + +/* + * We delay transactions when we've determined that the backend storage + * isn't able to accommodate the rate of incoming writes. + * + * If there is already a transaction waiting, we delay relative to when + * that transaction finishes waiting. This way the calculated min_time + * is independent of the number of threads concurrently executing + * transactions. + * + * If we are the only waiter, wait relative to when the transaction + * started, rather than the current time. This credits the transaction for + * "time already served", e.g. reading indirect blocks. + * + * The minimum time for a transaction to take is calculated as: + * min_time = scale * (dirty - min) / (max - dirty) + * min_time is then capped at zfs_delay_max_ns. + * + * The delay has two degrees of freedom that can be adjusted via tunables. + * The percentage of dirty data at which we start to delay is defined by + * zfs_delay_min_dirty_percent. This should typically be at or above + * zfs_vdev_async_write_active_max_dirty_percent so that we only start to + * delay after writing at full speed has failed to keep up with the incoming + * write rate. The scale of the curve is defined by zfs_delay_scale. Roughly + * speaking, this variable determines the amount of delay at the midpoint of + * the curve. + * + * delay + * 10ms +-------------------------------------------------------------*+ + * | *| + * 9ms + *+ + * | *| + * 8ms + *+ + * | * | + * 7ms + * + + * | * | + * 6ms + * + + * | * | + * 5ms + * + + * | * | + * 4ms + * + + * | * | + * 3ms + * + + * | * | + * 2ms + (midpoint) * + + * | | ** | + * 1ms + v *** + + * | zfs_delay_scale ----------> ******** | + * 0 +-------------------------------------*********----------------+ + * 0% <- zfs_dirty_data_max -> 100% + * + * Note that since the delay is added to the outstanding time remaining on the + * most recent transaction, the delay is effectively the inverse of IOPS. + * Here the midpoint of 500us translates to 2000 IOPS. The shape of the curve + * was chosen such that small changes in the amount of accumulated dirty data + * in the first 3/4 of the curve yield relatively small differences in the + * amount of delay. + * + * The effects can be easier to understand when the amount of delay is + * represented on a log scale: + * + * delay + * 100ms +-------------------------------------------------------------++ + * + + + * | | + * + *+ + * 10ms + *+ + * + ** + + * | (midpoint) ** | + * + | ** + + * 1ms + v **** + + * + zfs_delay_scale ----------> ***** + + * | **** | + * + **** + + * 100us + ** + + * + * + + * | * | + * + * + + * 10us + * + + * + + + * | | + * + + + * +--------------------------------------------------------------+ + * 0% <- zfs_dirty_data_max -> 100% + * + * Note here that only as the amount of dirty data approaches its limit does + * the delay start to increase rapidly. The goal of a properly tuned system + * should be to keep the amount of dirty data out of that range by first + * ensuring that the appropriate limits are set for the I/O scheduler to reach + * optimal throughput on the backend storage, and then by changing the value + * of zfs_delay_scale to increase the steepness of the curve. + */ +static void +dmu_tx_delay(dmu_tx_t *tx, uint64_t dirty) +{ + dsl_pool_t *dp = tx->tx_pool; + uint64_t delay_min_bytes = + zfs_dirty_data_max * zfs_delay_min_dirty_percent / 100; + hrtime_t wakeup, min_tx_time, now; + + if (dirty <= delay_min_bytes) + return; + + /* + * The caller has already waited until we are under the max. + * We make them pass us the amount of dirty data so we don't + * have to handle the case of it being >= the max, which could + * cause a divide-by-zero if it's == the max. + */ + ASSERT3U(dirty, <, zfs_dirty_data_max); + + now = gethrtime(); + min_tx_time = zfs_delay_scale * + (dirty - delay_min_bytes) / (zfs_dirty_data_max - dirty); + min_tx_time = MIN(min_tx_time, zfs_delay_max_ns); + if (now > tx->tx_start + min_tx_time) + return; + + DTRACE_PROBE3(delay__mintime, dmu_tx_t *, tx, uint64_t, dirty, + uint64_t, min_tx_time); + + mutex_enter(&dp->dp_lock); + wakeup = MAX(tx->tx_start + min_tx_time, + dp->dp_last_wakeup + min_tx_time); + dp->dp_last_wakeup = wakeup; + mutex_exit(&dp->dp_lock); + + zfs_sleep_until(wakeup); +} + static int dmu_tx_try_assign(dmu_tx_t *tx, txg_how_t txg_how) { @@ -965,6 +1104,13 @@ dmu_tx_try_assign(dmu_tx_t *tx, txg_how_t txg_how) return (SET_ERROR(ERESTART)); } + if (!tx->tx_waited && + dsl_pool_need_dirty_delay(tx->tx_pool)) { + tx->tx_wait_dirty = B_TRUE; + DMU_TX_STAT_BUMP(dmu_tx_dirty_delay); + return (ERESTART); + } + tx->tx_txg = txg_hold_open(tx->tx_pool, &tx->tx_txgh); tx->tx_needassign_txh = NULL; @@ -1092,6 +1238,10 @@ dmu_tx_unassign(dmu_tx_t *tx) * blocking, returns immediately with ERESTART. This should be used * whenever you're holding locks. On an ERESTART error, the caller * should drop locks, do a dmu_tx_wait(tx), and try again. + * + * (3) TXG_WAITED. Like TXG_NOWAIT, but indicates that dmu_tx_wait() + * has already been called on behalf of this operation (though + * most likely on a different tx). */ int dmu_tx_assign(dmu_tx_t *tx, txg_how_t txg_how) @@ -1100,11 +1250,15 @@ dmu_tx_assign(dmu_tx_t *tx, txg_how_t txg_how) int err; ASSERT(tx->tx_txg == 0); - ASSERT(txg_how == TXG_WAIT || txg_how == TXG_NOWAIT); + ASSERT(txg_how == TXG_WAIT || txg_how == TXG_NOWAIT || + txg_how == TXG_WAITED); ASSERT(!dsl_pool_sync_context(tx->tx_pool)); before = gethrtime(); + if (txg_how == TXG_WAITED) + tx->tx_waited = B_TRUE; + /* If we might wait, we must not hold the config lock. */ ASSERT(txg_how != TXG_WAIT || !dsl_pool_config_held(tx->tx_pool)); @@ -1128,17 +1282,47 @@ void dmu_tx_wait(dmu_tx_t *tx) { spa_t *spa = tx->tx_pool->dp_spa; + dsl_pool_t *dp = tx->tx_pool; ASSERT(tx->tx_txg == 0); ASSERT(!dsl_pool_config_held(tx->tx_pool)); - /* - * It's possible that the pool has become active after this thread - * has tried to obtain a tx. If that's the case then his - * tx_lasttried_txg would not have been assigned. - */ - if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) { - txg_wait_synced(tx->tx_pool, spa_last_synced_txg(spa) + 1); + if (tx->tx_wait_dirty) { + uint64_t dirty; + + /* + * dmu_tx_try_assign() has determined that we need to wait + * because we've consumed much or all of the dirty buffer + * space. + */ + mutex_enter(&dp->dp_lock); + if (dp->dp_dirty_total >= zfs_dirty_data_max) + DMU_TX_STAT_BUMP(dmu_tx_dirty_over_max); + while (dp->dp_dirty_total >= zfs_dirty_data_max) + cv_wait(&dp->dp_spaceavail_cv, &dp->dp_lock); + dirty = dp->dp_dirty_total; + mutex_exit(&dp->dp_lock); + + dmu_tx_delay(tx, dirty); + + tx->tx_wait_dirty = B_FALSE; + + /* + * Note: setting tx_waited only has effect if the caller + * used TX_WAIT. Otherwise they are going to destroy + * this tx and try again. The common case, zfs_write(), + * uses TX_WAIT. + */ + tx->tx_waited = B_TRUE; + } else if (spa_suspended(spa) || tx->tx_lasttried_txg == 0) { + /* + * If the pool is suspended we need to wait until it + * is resumed. Note that it's possible that the pool + * has become active after this thread has tried to + * obtain a tx. If that's the case then tx_lasttried_txg + * would not have been set. + */ + txg_wait_synced(dp, spa_last_synced_txg(spa) + 1); } else if (tx->tx_needassign_txh) { dnode_t *dn = tx->tx_needassign_txh->txh_dnode; @@ -1148,6 +1332,10 @@ dmu_tx_wait(dmu_tx_t *tx) mutex_exit(&dn->dn_mtx); tx->tx_needassign_txh = NULL; } else { + /* + * A dnode is assigned to the quiescing txg. Wait for its + * transaction to complete. + */ txg_wait_open(tx->tx_pool, tx->tx_lasttried_txg + 1); } } @@ -1268,7 +1456,6 @@ dmu_tx_pool(dmu_tx_t *tx) return (tx->tx_pool); } - void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *func, void *data) { diff --git a/module/zfs/dmu_zfetch.c b/module/zfs/dmu_zfetch.c index 705478c82..feb763947 100644 --- a/module/zfs/dmu_zfetch.c +++ b/module/zfs/dmu_zfetch.c @@ -23,6 +23,10 @@ * Use is subject to license terms. */ +/* + * Copyright (c) 2013 by Delphix. All rights reserved. + */ + #include <sys/zfs_context.h> #include <sys/dnode.h> #include <sys/dmu_objset.h> @@ -287,7 +291,7 @@ dmu_zfetch_fetch(dnode_t *dn, uint64_t blkid, uint64_t nblks) fetchsz = dmu_zfetch_fetchsz(dn, blkid, nblks); for (i = 0; i < fetchsz; i++) { - dbuf_prefetch(dn, blkid + i); + dbuf_prefetch(dn, blkid + i, ZIO_PRIORITY_ASYNC_READ); } return (fetchsz); diff --git a/module/zfs/dnode.c b/module/zfs/dnode.c index 7ac379578..25c77753b 100644 --- a/module/zfs/dnode.c +++ b/module/zfs/dnode.c @@ -1789,23 +1789,22 @@ dnode_diduse_space(dnode_t *dn, int64_t delta) } /* - * Call when we think we're going to write/free space in open context. - * Be conservative (ie. OK to write less than this or free more than - * this, but don't write more or free less). + * Call when we think we're going to write/free space in open context to track + * the amount of memory in use by the currently open txg. */ void dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) { objset_t *os = dn->dn_objset; dsl_dataset_t *ds = os->os_dsl_dataset; + int64_t aspace = spa_get_asize(os->os_spa, space); - if (space > 0) - space = spa_get_asize(os->os_spa, space); - - if (ds) - dsl_dir_willuse_space(ds->ds_dir, space, tx); + if (ds != NULL) { + dsl_dir_willuse_space(ds->ds_dir, aspace, tx); + dsl_pool_dirty_space(dmu_tx_pool(tx), space, tx); + } - dmu_tx_willuse_space(tx, space); + dmu_tx_willuse_space(tx, aspace); } /* diff --git a/module/zfs/dsl_dir.c b/module/zfs/dsl_dir.c index 44795f344..54a7dffb1 100644 --- a/module/zfs/dsl_dir.c +++ b/module/zfs/dsl_dir.c @@ -589,7 +589,6 @@ dsl_dir_space_available(dsl_dir_t *dd, struct tempreserve { list_node_t tr_node; - dsl_pool_t *tr_dp; dsl_dir_t *tr_ds; uint64_t tr_size; }; @@ -740,25 +739,24 @@ dsl_dir_tempreserve_space(dsl_dir_t *dd, uint64_t lsize, uint64_t asize, tr = kmem_zalloc(sizeof (struct tempreserve), KM_PUSHPAGE); tr->tr_size = lsize; list_insert_tail(tr_list, tr); - - err = dsl_pool_tempreserve_space(dd->dd_pool, asize, tx); } else { if (err == EAGAIN) { + /* + * If arc_memory_throttle() detected that pageout + * is running and we are low on memory, we delay new + * non-pageout transactions to give pageout an + * advantage. + * + * It is unfortunate to be delaying while the caller's + * locks are held. + */ txg_delay(dd->dd_pool, tx->tx_txg, MSEC2NSEC(10), MSEC2NSEC(10)); err = SET_ERROR(ERESTART); } - dsl_pool_memory_pressure(dd->dd_pool); } if (err == 0) { - struct tempreserve *tr; - - tr = kmem_zalloc(sizeof (struct tempreserve), KM_PUSHPAGE); - tr->tr_dp = dd->dd_pool; - tr->tr_size = asize; - list_insert_tail(tr_list, tr); - err = dsl_dir_tempreserve_impl(dd, asize, fsize >= asize, FALSE, asize > usize, tr_list, tx, TRUE); } @@ -787,10 +785,8 @@ dsl_dir_tempreserve_clear(void *tr_cookie, dmu_tx_t *tx) if (tr_cookie == NULL) return; - while ((tr = list_head(tr_list))) { - if (tr->tr_dp) { - dsl_pool_tempreserve_clear(tr->tr_dp, tr->tr_size, tx); - } else if (tr->tr_ds) { + while ((tr = list_head(tr_list)) != NULL) { + if (tr->tr_ds) { mutex_enter(&tr->tr_ds->dd_lock); ASSERT3U(tr->tr_ds->dd_tempreserved[txgidx], >=, tr->tr_size); @@ -806,8 +802,14 @@ dsl_dir_tempreserve_clear(void *tr_cookie, dmu_tx_t *tx) kmem_free(tr_list, sizeof (list_t)); } -static void -dsl_dir_willuse_space_impl(dsl_dir_t *dd, int64_t space, dmu_tx_t *tx) +/* + * This should be called from open context when we think we're going to write + * or free space, for example when dirtying data. Be conservative; it's okay + * to write less space or free more, but we don't want to write more or free + * less than the amount specified. + */ +void +dsl_dir_willuse_space(dsl_dir_t *dd, int64_t space, dmu_tx_t *tx) { int64_t parent_space; uint64_t est_used; @@ -825,19 +827,7 @@ dsl_dir_willuse_space_impl(dsl_dir_t *dd, int64_t space, dmu_tx_t *tx) /* XXX this is potentially expensive and unnecessary... */ if (parent_space && dd->dd_parent) - dsl_dir_willuse_space_impl(dd->dd_parent, parent_space, tx); -} - -/* - * Call in open context when we think we're going to write/free space, - * eg. when dirtying data. Be conservative (ie. OK to write less than - * this or free more than this, but don't write more or free less). - */ -void -dsl_dir_willuse_space(dsl_dir_t *dd, int64_t space, dmu_tx_t *tx) -{ - dsl_pool_willuse_space(dd->dd_pool, space, tx); - dsl_dir_willuse_space_impl(dd, space, tx); + dsl_dir_willuse_space(dd->dd_parent, parent_space, tx); } /* call from syncing context when we actually write/free space for this dd */ diff --git a/module/zfs/dsl_pool.c b/module/zfs/dsl_pool.c index e7127c535..eed4bd497 100644 --- a/module/zfs/dsl_pool.c +++ b/module/zfs/dsl_pool.c @@ -46,18 +46,85 @@ #include <sys/zil_impl.h> #include <sys/dsl_userhold.h> -int zfs_no_write_throttle = 0; -int zfs_write_limit_shift = 3; /* 1/8th of physical memory */ -int zfs_txg_synctime_ms = 1000; /* target millisecs to sync a txg */ +/* + * ZFS Write Throttle + * ------------------ + * + * ZFS must limit the rate of incoming writes to the rate at which it is able + * to sync data modifications to the backend storage. Throttling by too much + * creates an artificial limit; throttling by too little can only be sustained + * for short periods and would lead to highly lumpy performance. On a per-pool + * basis, ZFS tracks the amount of modified (dirty) data. As operations change + * data, the amount of dirty data increases; as ZFS syncs out data, the amount + * of dirty data decreases. When the amount of dirty data exceeds a + * predetermined threshold further modifications are blocked until the amount + * of dirty data decreases (as data is synced out). + * + * The limit on dirty data is tunable, and should be adjusted according to + * both the IO capacity and available memory of the system. The larger the + * window, the more ZFS is able to aggregate and amortize metadata (and data) + * changes. However, memory is a limited resource, and allowing for more dirty + * data comes at the cost of keeping other useful data in memory (for example + * ZFS data cached by the ARC). + * + * Implementation + * + * As buffers are modified dsl_pool_willuse_space() increments both the per- + * txg (dp_dirty_pertxg[]) and poolwide (dp_dirty_total) accounting of + * dirty space used; dsl_pool_dirty_space() decrements those values as data + * is synced out from dsl_pool_sync(). While only the poolwide value is + * relevant, the per-txg value is useful for debugging. The tunable + * zfs_dirty_data_max determines the dirty space limit. Once that value is + * exceeded, new writes are halted until space frees up. + * + * The zfs_dirty_data_sync tunable dictates the threshold at which we + * ensure that there is a txg syncing (see the comment in txg.c for a full + * description of transaction group stages). + * + * The IO scheduler uses both the dirty space limit and current amount of + * dirty data as inputs. Those values affect the number of concurrent IOs ZFS + * issues. See the comment in vdev_queue.c for details of the IO scheduler. + * + * The delay is also calculated based on the amount of dirty data. See the + * comment above dmu_tx_delay() for details. + */ + +/* + * zfs_dirty_data_max will be set to zfs_dirty_data_max_percent% of all memory, + * capped at zfs_dirty_data_max_max. It can also be overridden with a module + * parameter. + */ +unsigned long zfs_dirty_data_max = 0; +unsigned long zfs_dirty_data_max_max = 0; +int zfs_dirty_data_max_percent = 10; +int zfs_dirty_data_max_max_percent = 25; -unsigned long zfs_write_limit_min = 32 << 20; /* min write limit is 32MB */ -unsigned long zfs_write_limit_max = 0; /* max data payload per txg */ -unsigned long zfs_write_limit_inflated = 0; -unsigned long zfs_write_limit_override = 0; +/* + * If there is at least this much dirty data, push out a txg. + */ +unsigned long zfs_dirty_data_sync = 64 * 1024 * 1024; -kmutex_t zfs_write_limit_lock; +/* + * Once there is this amount of dirty data, the dmu_tx_delay() will kick in + * and delay each transaction. + * This value should be >= zfs_vdev_async_write_active_max_dirty_percent. + */ +int zfs_delay_min_dirty_percent = 60; -static pgcnt_t old_physmem = 0; +/* + * This controls how quickly the delay approaches infinity. + * Larger values cause it to delay more for a given amount of dirty data. + * Therefore larger values will cause there to be less dirty data for a + * given throughput. + * + * For the smoothest delay, this value should be about 1 billion divided + * by the maximum number of operations per second. This will smoothly + * handle between 10x and 1/10th this number. + * + * Note: zfs_delay_scale * zfs_dirty_data_max must be < 2^64, due to the + * multiply in dmu_tx_delay(). + */ +unsigned long zfs_delay_scale = 1000 * 1000 * 1000 / 2000; hrtime_t zfs_throttle_delay = MSEC2NSEC(10); hrtime_t zfs_throttle_resolution = MSEC2NSEC(10); @@ -87,7 +154,6 @@ dsl_pool_open_impl(spa_t *spa, uint64_t txg) dp->dp_spa = spa; dp->dp_meta_rootbp = *bp; rrw_init(&dp->dp_config_rwlock, B_TRUE); - dp->dp_write_limit = zfs_write_limit_min; txg_init(dp, txg); txg_list_create(&dp->dp_dirty_datasets, @@ -100,6 +166,7 @@ dsl_pool_open_impl(spa_t *spa, uint64_t txg) offsetof(dsl_sync_task_t, dst_node)); mutex_init(&dp->dp_lock, NULL, MUTEX_DEFAULT, NULL); + cv_init(&dp->dp_spaceavail_cv, NULL, CV_DEFAULT, NULL); dp->dp_iput_taskq = taskq_create("zfs_iput_taskq", 1, minclsyspri, 1, 4, 0); @@ -214,9 +281,9 @@ out: void dsl_pool_close(dsl_pool_t *dp) { - /* drop our references from dsl_pool_open() */ - /* + * Drop our references from dsl_pool_open(). + * * Since we held the origin_snap from "syncing" context (which * includes pool-opening context), it actually only got a "ref" * and not a hold, so just drop that here. @@ -346,6 +413,34 @@ deadlist_enqueue_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx) return (0); } +static void +dsl_pool_sync_mos(dsl_pool_t *dp, dmu_tx_t *tx) +{ + zio_t *zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); + dmu_objset_sync(dp->dp_meta_objset, zio, tx); + VERIFY0(zio_wait(zio)); + dprintf_bp(&dp->dp_meta_rootbp, "meta objset rootbp is %s", ""); + spa_set_rootblkptr(dp->dp_spa, &dp->dp_meta_rootbp); +} + +static void +dsl_pool_dirty_delta(dsl_pool_t *dp, int64_t delta) +{ + ASSERT(MUTEX_HELD(&dp->dp_lock)); + + if (delta < 0) + ASSERT3U(-delta, <=, dp->dp_dirty_total); + + dp->dp_dirty_total += delta; + + /* + * Note: we signal even when increasing dp_dirty_total. + * This ensures forward progress -- each thread wakes the next waiter. + */ + if (dp->dp_dirty_total <= zfs_dirty_data_max) + cv_signal(&dp->dp_spaceavail_cv); +} + void dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) { @@ -354,29 +449,18 @@ dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) dsl_dir_t *dd; dsl_dataset_t *ds; objset_t *mos = dp->dp_meta_objset; - hrtime_t start, write_time; - uint64_t data_written; - int err; list_t synced_datasets; list_create(&synced_datasets, sizeof (dsl_dataset_t), offsetof(dsl_dataset_t, ds_synced_link)); - /* - * We need to copy dp_space_towrite() before doing - * dsl_sync_task_sync(), because - * dsl_dataset_snapshot_reserve_space() will increase - * dp_space_towrite but not actually write anything. - */ - data_written = dp->dp_space_towrite[txg & TXG_MASK]; - tx = dmu_tx_create_assigned(dp, txg); - dp->dp_read_overhead = 0; - start = gethrtime(); - + /* + * Write out all dirty blocks of dirty datasets. + */ zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); - while ((ds = txg_list_remove(&dp->dp_dirty_datasets, txg))) { + while ((ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) != NULL) { /* * We must not sync any non-MOS datasets twice, because * we may have taken a snapshot of them. However, we @@ -386,20 +470,25 @@ dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) list_insert_tail(&synced_datasets, ds); dsl_dataset_sync(ds, zio, tx); } - DTRACE_PROBE(pool_sync__1setup); - err = zio_wait(zio); + VERIFY0(zio_wait(zio)); - write_time = gethrtime() - start; - ASSERT(err == 0); - DTRACE_PROBE(pool_sync__2rootzio); + /* + * We have written all of the accounted dirty data, so our + * dp_space_towrite should now be zero. However, some seldom-used + * code paths do not adhere to this (e.g. dbuf_undirty(), also + * rounding error in dbuf_write_physdone). + * Shore up the accounting of any dirtied space now. + */ + dsl_pool_undirty_space(dp, dp->dp_dirty_pertxg[txg & TXG_MASK], txg); /* * After the data blocks have been written (ensured by the zio_wait() * above), update the user/group space accounting. */ - for (ds = list_head(&synced_datasets); ds; - ds = list_next(&synced_datasets, ds)) + for (ds = list_head(&synced_datasets); ds != NULL; + ds = list_next(&synced_datasets, ds)) { dmu_objset_do_userquota_updates(ds->ds_objset, tx); + } /* * Sync the datasets again to push out the changes due to @@ -409,12 +498,12 @@ dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) * about which blocks are part of the snapshot). */ zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); - while ((ds = txg_list_remove(&dp->dp_dirty_datasets, txg))) { + while ((ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) != NULL) { ASSERT(list_link_active(&ds->ds_synced_link)); dmu_buf_rele(ds->ds_dbuf, ds); dsl_dataset_sync(ds, zio, tx); } - err = zio_wait(zio); + VERIFY0(zio_wait(zio)); /* * Now that the datasets have been completely synced, we can @@ -423,7 +512,7 @@ dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) * - move dead blocks from the pending deadlist to the on-disk deadlist * - release hold from dsl_dataset_dirty() */ - while ((ds = list_remove_head(&synced_datasets))) { + while ((ds = list_remove_head(&synced_datasets)) != NULL) { ASSERTV(objset_t *os = ds->ds_objset); bplist_iterate(&ds->ds_pending_deadlist, deadlist_enqueue_cb, &ds->ds_deadlist, tx); @@ -431,10 +520,9 @@ dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) dmu_buf_rele(ds->ds_dbuf, ds); } - start = gethrtime(); - while ((dd = txg_list_remove(&dp->dp_dirty_dirs, txg))) + while ((dd = txg_list_remove(&dp->dp_dirty_dirs, txg)) != NULL) { dsl_dir_sync(dd, tx); - write_time += gethrtime() - start; + } /* * The MOS's space is accounted for in the pool/$MOS @@ -452,20 +540,10 @@ dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) dp->dp_mos_uncompressed_delta = 0; } - start = gethrtime(); if (list_head(&mos->os_dirty_dnodes[txg & TXG_MASK]) != NULL || list_head(&mos->os_free_dnodes[txg & TXG_MASK]) != NULL) { - zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); - dmu_objset_sync(mos, zio, tx); - err = zio_wait(zio); - ASSERT(err == 0); - dprintf_bp(&dp->dp_meta_rootbp, "meta objset rootbp is %s", ""); - spa_set_rootblkptr(dp->dp_spa, &dp->dp_meta_rootbp); + dsl_pool_sync_mos(dp, tx); } - write_time += gethrtime() - start; - DTRACE_PROBE2(pool_sync__4io, hrtime_t, write_time, - hrtime_t, dp->dp_read_overhead); - write_time -= dp->dp_read_overhead; /* * If we modify a dataset in the same txg that we want to destroy it, @@ -476,72 +554,29 @@ dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) * The MOS data dirtied by the sync_tasks will be synced on the next * pass. */ - DTRACE_PROBE(pool_sync__3task); if (!txg_list_empty(&dp->dp_sync_tasks, txg)) { dsl_sync_task_t *dst; /* * No more sync tasks should have been added while we * were syncing. */ - ASSERT(spa_sync_pass(dp->dp_spa) == 1); - while ((dst = txg_list_remove(&dp->dp_sync_tasks, txg))) + ASSERT3U(spa_sync_pass(dp->dp_spa), ==, 1); + while ((dst = txg_list_remove(&dp->dp_sync_tasks, txg)) != NULL) dsl_sync_task_sync(dst, tx); } dmu_tx_commit(tx); - dp->dp_space_towrite[txg & TXG_MASK] = 0; - ASSERT(dp->dp_tempreserved[txg & TXG_MASK] == 0); - - /* - * If the write limit max has not been explicitly set, set it - * to a fraction of available physical memory (default 1/8th). - * Note that we must inflate the limit because the spa - * inflates write sizes to account for data replication. - * Check this each sync phase to catch changing memory size. - */ - if (physmem != old_physmem && zfs_write_limit_shift) { - mutex_enter(&zfs_write_limit_lock); - old_physmem = physmem; - zfs_write_limit_max = ptob(physmem) >> zfs_write_limit_shift; - zfs_write_limit_inflated = MAX(zfs_write_limit_min, - spa_get_asize(dp->dp_spa, zfs_write_limit_max)); - mutex_exit(&zfs_write_limit_lock); - } - - /* - * Attempt to keep the sync time consistent by adjusting the - * amount of write traffic allowed into each transaction group. - * Weight the throughput calculation towards the current value: - * thru = 3/4 old_thru + 1/4 new_thru - * - * Note: write_time is in nanosecs while dp_throughput is expressed in - * bytes per millisecond. - */ - ASSERT(zfs_write_limit_min > 0); - if (data_written > zfs_write_limit_min / 8 && - write_time > MSEC2NSEC(1)) { - uint64_t throughput = data_written / NSEC2MSEC(write_time); - - if (dp->dp_throughput) - dp->dp_throughput = throughput / 4 + - 3 * dp->dp_throughput / 4; - else - dp->dp_throughput = throughput; - dp->dp_write_limit = MIN(zfs_write_limit_inflated, - MAX(zfs_write_limit_min, - dp->dp_throughput * zfs_txg_synctime_ms)); - } + DTRACE_PROBE2(dsl_pool_sync__done, dsl_pool_t *dp, dp, uint64_t, txg); } void dsl_pool_sync_done(dsl_pool_t *dp, uint64_t txg) { zilog_t *zilog; - dsl_dataset_t *ds; while ((zilog = txg_list_remove(&dp->dp_dirty_zilogs, txg))) { - ds = dmu_objset_ds(zilog->zl_os); + dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); zil_clean(zilog, txg); ASSERT(!dmu_objset_is_dirty(zilog->zl_os, txg)); dmu_buf_rele(ds->ds_dbuf, zilog); @@ -583,84 +618,49 @@ dsl_pool_adjustedsize(dsl_pool_t *dp, boolean_t netfree) return (space - resv); } -int -dsl_pool_tempreserve_space(dsl_pool_t *dp, uint64_t space, dmu_tx_t *tx) +boolean_t +dsl_pool_need_dirty_delay(dsl_pool_t *dp) { - uint64_t reserved = 0; - uint64_t write_limit = (zfs_write_limit_override ? - zfs_write_limit_override : dp->dp_write_limit); - - if (zfs_no_write_throttle) { - atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK], - space); - return (0); - } - - /* - * Check to see if we have exceeded the maximum allowed IO for - * this transaction group. We can do this without locks since - * a little slop here is ok. Note that we do the reserved check - * with only half the requested reserve: this is because the - * reserve requests are worst-case, and we really don't want to - * throttle based off of worst-case estimates. - */ - if (write_limit > 0) { - reserved = dp->dp_space_towrite[tx->tx_txg & TXG_MASK] - + dp->dp_tempreserved[tx->tx_txg & TXG_MASK] / 2; + uint64_t delay_min_bytes = + zfs_dirty_data_max * zfs_delay_min_dirty_percent / 100; + boolean_t rv; - if (reserved && reserved > write_limit) { - DMU_TX_STAT_BUMP(dmu_tx_write_limit); - return (SET_ERROR(ERESTART)); - } - } - - atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK], space); - - /* - * If this transaction group is over 7/8ths capacity, delay - * the caller 1 clock tick. This will slow down the "fill" - * rate until the sync process can catch up with us. - */ - if (reserved && reserved > (write_limit - (write_limit >> 3))) { - txg_delay(dp, tx->tx_txg, zfs_throttle_delay, - zfs_throttle_resolution); - } - - return (0); + mutex_enter(&dp->dp_lock); + if (dp->dp_dirty_total > zfs_dirty_data_sync) + txg_kick(dp); + rv = (dp->dp_dirty_total > delay_min_bytes); + mutex_exit(&dp->dp_lock); + return (rv); } void -dsl_pool_tempreserve_clear(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx) +dsl_pool_dirty_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx) { - ASSERT(dp->dp_tempreserved[tx->tx_txg & TXG_MASK] >= space); - atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK], -space); + if (space > 0) { + mutex_enter(&dp->dp_lock); + dp->dp_dirty_pertxg[tx->tx_txg & TXG_MASK] += space; + dsl_pool_dirty_delta(dp, space); + mutex_exit(&dp->dp_lock); + } } void -dsl_pool_memory_pressure(dsl_pool_t *dp) +dsl_pool_undirty_space(dsl_pool_t *dp, int64_t space, uint64_t txg) { - uint64_t space_inuse = 0; - int i; - - if (dp->dp_write_limit == zfs_write_limit_min) + ASSERT3S(space, >=, 0); + if (space == 0) return; - for (i = 0; i < TXG_SIZE; i++) { - space_inuse += dp->dp_space_towrite[i]; - space_inuse += dp->dp_tempreserved[i]; - } - dp->dp_write_limit = MAX(zfs_write_limit_min, - MIN(dp->dp_write_limit, space_inuse / 4)); -} - -void -dsl_pool_willuse_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx) -{ - if (space > 0) { - mutex_enter(&dp->dp_lock); - dp->dp_space_towrite[tx->tx_txg & TXG_MASK] += space; - mutex_exit(&dp->dp_lock); + mutex_enter(&dp->dp_lock); + if (dp->dp_dirty_pertxg[txg & TXG_MASK] < space) { + /* XXX writing something we didn't dirty? */ + space = dp->dp_dirty_pertxg[txg & TXG_MASK]; } + ASSERT3U(dp->dp_dirty_pertxg[txg & TXG_MASK], >=, space); + dp->dp_dirty_pertxg[txg & TXG_MASK] -= space; + ASSERT3U(dp->dp_dirty_total, >=, space); + dsl_pool_dirty_delta(dp, -space); + mutex_exit(&dp->dp_lock); } /* ARGSUSED */ @@ -1049,24 +1049,30 @@ dsl_pool_config_held(dsl_pool_t *dp) EXPORT_SYMBOL(dsl_pool_config_enter); EXPORT_SYMBOL(dsl_pool_config_exit); -module_param(zfs_no_write_throttle, int, 0644); -MODULE_PARM_DESC(zfs_no_write_throttle, "Disable write throttling"); +/* zfs_dirty_data_max_percent only applied at module load time in arc_init(). */ +module_param(zfs_dirty_data_max_percent, int, 0444); +MODULE_PARM_DESC(zfs_dirty_data_max_percent, "percent of ram can be dirty"); -module_param(zfs_write_limit_shift, int, 0444); -MODULE_PARM_DESC(zfs_write_limit_shift, "log2(fraction of memory) per txg"); +/* zfs_dirty_data_max_max_percent only applied at module load time in + * arc_init(). */ +module_param(zfs_dirty_data_max_max_percent, int, 0444); +MODULE_PARM_DESC(zfs_dirty_data_max_max_percent, + "zfs_dirty_data_max upper bound as % of RAM"); -module_param(zfs_txg_synctime_ms, int, 0644); -MODULE_PARM_DESC(zfs_txg_synctime_ms, "Target milliseconds between txg sync"); +module_param(zfs_delay_min_dirty_percent, int, 0644); +MODULE_PARM_DESC(zfs_delay_min_dirty_percent, "transaction delay threshold"); -module_param(zfs_write_limit_min, ulong, 0444); -MODULE_PARM_DESC(zfs_write_limit_min, "Min txg write limit"); +module_param(zfs_dirty_data_max, ulong, 0644); +MODULE_PARM_DESC(zfs_dirty_data_max, "determines the dirty space limit"); -module_param(zfs_write_limit_max, ulong, 0444); -MODULE_PARM_DESC(zfs_write_limit_max, "Max txg write limit"); +/* zfs_dirty_data_max_max only applied at module load time in arc_init(). */ +module_param(zfs_dirty_data_max_max, ulong, 0444); +MODULE_PARM_DESC(zfs_dirty_data_max_max, + "zfs_dirty_data_max upper bound in bytes"); -module_param(zfs_write_limit_inflated, ulong, 0444); -MODULE_PARM_DESC(zfs_write_limit_inflated, "Inflated txg write limit"); +module_param(zfs_dirty_data_sync, ulong, 0644); +MODULE_PARM_DESC(zfs_dirty_data_sync, "sync txg when this much dirty data"); -module_param(zfs_write_limit_override, ulong, 0444); -MODULE_PARM_DESC(zfs_write_limit_override, "Override txg write limit"); +module_param(zfs_delay_scale, ulong, 0644); +MODULE_PARM_DESC(zfs_delay_scale, "how quickly delay approaches infinity"); #endif diff --git a/module/zfs/dsl_scan.c b/module/zfs/dsl_scan.c index 354d5b1df..3780aee79 100644 --- a/module/zfs/dsl_scan.c +++ b/module/zfs/dsl_scan.c @@ -1650,7 +1650,6 @@ dsl_scan_scrub_cb(dsl_pool_t *dp, uint64_t phys_birth = BP_PHYSICAL_BIRTH(bp); boolean_t needs_io = B_FALSE; int zio_flags = ZIO_FLAG_SCAN_THREAD | ZIO_FLAG_RAW | ZIO_FLAG_CANFAIL; - int zio_priority = 0; int scan_delay = 0; int d; @@ -1663,13 +1662,11 @@ dsl_scan_scrub_cb(dsl_pool_t *dp, ASSERT(DSL_SCAN_IS_SCRUB_RESILVER(scn)); if (scn->scn_phys.scn_func == POOL_SCAN_SCRUB) { zio_flags |= ZIO_FLAG_SCRUB; - zio_priority = ZIO_PRIORITY_SCRUB; needs_io = B_TRUE; scan_delay = zfs_scrub_delay; } else { ASSERT3U(scn->scn_phys.scn_func, ==, POOL_SCAN_RESILVER); zio_flags |= ZIO_FLAG_RESILVER; - zio_priority = ZIO_PRIORITY_RESILVER; needs_io = B_FALSE; scan_delay = zfs_resilver_delay; } @@ -1727,7 +1724,7 @@ dsl_scan_scrub_cb(dsl_pool_t *dp, delay(scan_delay); zio_nowait(zio_read(NULL, spa, bp, data, size, - dsl_scan_scrub_done, NULL, zio_priority, + dsl_scan_scrub_done, NULL, ZIO_PRIORITY_SCRUB, zio_flags, zb)); } diff --git a/module/zfs/spa.c b/module/zfs/spa.c index c7ea59536..3daf5805d 100644 --- a/module/zfs/spa.c +++ b/module/zfs/spa.c @@ -83,7 +83,6 @@ typedef enum zti_modes { ZTI_MODE_FIXED, /* value is # of threads (min 1) */ - ZTI_MODE_ONLINE_PERCENT, /* value is % of online CPUs */ ZTI_MODE_BATCH, /* cpu-intensive; value is ignored */ ZTI_MODE_NULL, /* don't create a taskq */ ZTI_NMODES @@ -142,7 +141,7 @@ static inline int spa_load_impl(spa_t *spa, uint64_t, nvlist_t *config, char **ereport); static void spa_vdev_resilver_done(spa_t *spa); -uint_t zio_taskq_batch_pct = 100; /* 1 thread per cpu in pset */ +uint_t zio_taskq_batch_pct = 75; /* 1 thread per cpu in pset */ id_t zio_taskq_psrset_bind = PS_NONE; boolean_t zio_taskq_sysdc = B_TRUE; /* use SDC scheduling class */ uint_t zio_taskq_basedc = 80; /* base duty cycle */ @@ -837,31 +836,27 @@ spa_taskqs_init(spa_t *spa, zio_type_t t, zio_taskq_type_t q) tqs->stqs_count = count; tqs->stqs_taskq = kmem_alloc(count * sizeof (taskq_t *), KM_SLEEP); - for (i = 0; i < count; i++) { - taskq_t *tq; - - switch (mode) { - case ZTI_MODE_FIXED: - ASSERT3U(value, >=, 1); - value = MAX(value, 1); - break; + switch (mode) { + case ZTI_MODE_FIXED: + ASSERT3U(value, >=, 1); + value = MAX(value, 1); + break; - case ZTI_MODE_BATCH: - batch = B_TRUE; - flags |= TASKQ_THREADS_CPU_PCT; - value = zio_taskq_batch_pct; - break; + case ZTI_MODE_BATCH: + batch = B_TRUE; + flags |= TASKQ_THREADS_CPU_PCT; + value = zio_taskq_batch_pct; + break; - case ZTI_MODE_ONLINE_PERCENT: - flags |= TASKQ_THREADS_CPU_PCT; - break; + default: + panic("unrecognized mode for %s_%s taskq (%u:%u) in " + "spa_activate()", + zio_type_name[t], zio_taskq_types[q], mode, value); + break; + } - default: - panic("unrecognized mode for %s_%s taskq (%u:%u) in " - "spa_activate()", - zio_type_name[t], zio_taskq_types[q], mode, value); - break; - } + for (i = 0; i < count; i++) { + taskq_t *tq; if (count > 1) { (void) snprintf(name, sizeof (name), "%s_%s_%u", @@ -878,7 +873,16 @@ spa_taskqs_init(spa_t *spa, zio_type_t t, zio_taskq_type_t q) tq = taskq_create_sysdc(name, value, 50, INT_MAX, spa->spa_proc, zio_taskq_basedc, flags); } else { - tq = taskq_create_proc(name, value, maxclsyspri, 50, + pri_t pri = maxclsyspri; + /* + * The write issue taskq can be extremely CPU + * intensive. Run it at slightly lower priority + * than the other taskqs. + */ + if (t == ZIO_TYPE_WRITE && q == ZIO_TASKQ_ISSUE) + pri--; + + tq = taskq_create_proc(name, value, pri, 50, INT_MAX, spa->spa_proc, flags); } @@ -5775,6 +5779,31 @@ spa_free_sync_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx) return (0); } +/* + * Note: this simple function is not inlined to make it easier to dtrace the + * amount of time spent syncing frees. + */ +static void +spa_sync_frees(spa_t *spa, bplist_t *bpl, dmu_tx_t *tx) +{ + zio_t *zio = zio_root(spa, NULL, NULL, 0); + bplist_iterate(bpl, spa_free_sync_cb, zio, tx); + VERIFY(zio_wait(zio) == 0); +} + +/* + * Note: this simple function is not inlined to make it easier to dtrace the + * amount of time spent syncing deferred frees. + */ +static void +spa_sync_deferred_frees(spa_t *spa, dmu_tx_t *tx) +{ + zio_t *zio = zio_root(spa, NULL, NULL, 0); + VERIFY3U(bpobj_iterate(&spa->spa_deferred_bpobj, + spa_free_sync_cb, zio, tx), ==, 0); + VERIFY0(zio_wait(zio)); +} + static void spa_sync_nvlist(spa_t *spa, uint64_t obj, nvlist_t *nv, dmu_tx_t *tx) { @@ -6102,7 +6131,6 @@ spa_sync(spa_t *spa, uint64_t txg) { dsl_pool_t *dp = spa->spa_dsl_pool; objset_t *mos = spa->spa_meta_objset; - bpobj_t *defer_bpo = &spa->spa_deferred_bpobj; bplist_t *free_bpl = &spa->spa_free_bplist[txg & TXG_MASK]; vdev_t *rvd = spa->spa_root_vdev; vdev_t *vd; @@ -6185,10 +6213,7 @@ spa_sync(spa_t *spa, uint64_t txg) !txg_list_empty(&dp->dp_sync_tasks, txg) || ((dsl_scan_active(dp->dp_scan) || txg_sync_waiting(dp)) && !spa_shutting_down(spa))) { - zio_t *zio = zio_root(spa, NULL, NULL, 0); - VERIFY3U(bpobj_iterate(defer_bpo, - spa_free_sync_cb, zio, tx), ==, 0); - VERIFY0(zio_wait(zio)); + spa_sync_deferred_frees(spa, tx); } /* @@ -6206,13 +6231,10 @@ spa_sync(spa_t *spa, uint64_t txg) dsl_pool_sync(dp, txg); if (pass < zfs_sync_pass_deferred_free) { - zio_t *zio = zio_root(spa, NULL, NULL, 0); - bplist_iterate(free_bpl, spa_free_sync_cb, - zio, tx); - VERIFY(zio_wait(zio) == 0); + spa_sync_frees(spa, free_bpl, tx); } else { bplist_iterate(free_bpl, bpobj_enqueue_cb, - defer_bpo, tx); + &spa->spa_deferred_bpobj, tx); } ddt_sync(spa, txg); diff --git a/module/zfs/spa_misc.c b/module/zfs/spa_misc.c index 91e7fdf35..d12e233b1 100644 --- a/module/zfs/spa_misc.c +++ b/module/zfs/spa_misc.c @@ -238,15 +238,14 @@ kmem_cache_t *spa_buffer_pool; int spa_mode_global; /* - * Expiration time in units of zfs_txg_synctime_ms. This value has two - * meanings. First it is used to determine when the spa_deadman logic - * should fire. By default the spa_deadman will fire if spa_sync has - * not completed in 1000 * zfs_txg_synctime_ms (i.e. 1000 seconds). - * Secondly, the value determines if an I/O is considered "hung". - * Any I/O that has not completed in zfs_deadman_synctime is considered - * "hung" resulting in a zevent being posted. + * Expiration time in milliseconds. This value has two meanings. First it is + * used to determine when the spa_deadman() logic should fire. By default the + * spa_deadman() will fire if spa_sync() has not completed in 1000 seconds. + * Secondly, the value determines if an I/O is considered "hung". Any I/O that + * has not completed in zfs_deadman_synctime_ms is considered "hung" resulting + * in a system panic. */ -unsigned long zfs_deadman_synctime = 1000ULL; +unsigned long zfs_deadman_synctime_ms = 1000000ULL; /* * By default the deadman is enabled. @@ -254,6 +253,17 @@ unsigned long zfs_deadman_synctime = 1000ULL; int zfs_deadman_enabled = 1; /* + * The worst case is single-sector max-parity RAID-Z blocks, in which + * case the space requirement is exactly (VDEV_RAIDZ_MAXPARITY + 1) + * times the size; so just assume that. Add to this the fact that + * we can have up to 3 DVAs per bp, and one more factor of 2 because + * the block may be dittoed with up to 3 DVAs by ddt_sync(). All together, + * the worst case is: + * (VDEV_RAIDZ_MAXPARITY + 1) * SPA_DVAS_PER_BP * 2 == 24 + */ +int spa_asize_inflation = 24; + +/* * ========================================================================== * SPA config locking * ========================================================================== @@ -489,8 +499,7 @@ spa_add(const char *name, nvlist_t *config, const char *altroot) spa->spa_proc = &p0; spa->spa_proc_state = SPA_PROC_NONE; - spa->spa_deadman_synctime = MSEC2NSEC(zfs_deadman_synctime * - zfs_txg_synctime_ms); + spa->spa_deadman_synctime = MSEC2NSEC(zfs_deadman_synctime_ms); refcount_create(&spa->spa_refcount); spa_config_lock_init(spa); @@ -1452,14 +1461,7 @@ spa_freeze_txg(spa_t *spa) uint64_t spa_get_asize(spa_t *spa, uint64_t lsize) { - /* - * The worst case is single-sector max-parity RAID-Z blocks, in which - * case the space requirement is exactly (VDEV_RAIDZ_MAXPARITY + 1) - * times the size; so just assume that. Add to this the fact that - * we can have up to 3 DVAs per bp, and one more factor of 2 because - * the block may be dittoed with up to 3 DVAs by ddt_sync(). - */ - return (lsize * (VDEV_RAIDZ_MAXPARITY + 1) * SPA_DVAS_PER_BP * 2); + return (lsize * spa_asize_inflation); } uint64_t @@ -1880,9 +1882,13 @@ EXPORT_SYMBOL(spa_mode); EXPORT_SYMBOL(spa_namespace_lock); -module_param(zfs_deadman_synctime, ulong, 0644); -MODULE_PARM_DESC(zfs_deadman_synctime,"Expire in units of zfs_txg_synctime_ms"); +module_param(zfs_deadman_synctime_ms, ulong, 0644); +MODULE_PARM_DESC(zfs_deadman_synctime_ms,"Expiration time in milliseconds"); module_param(zfs_deadman_enabled, int, 0644); MODULE_PARM_DESC(zfs_deadman_enabled, "Enable deadman timer"); + +module_param(spa_asize_inflation, int, 0644); +MODULE_PARM_DESC(spa_asize_inflation, + "SPA size estimate multiplication factor"); #endif diff --git a/module/zfs/txg.c b/module/zfs/txg.c index 8d410f7a5..9a594b954 100644 --- a/module/zfs/txg.c +++ b/module/zfs/txg.c @@ -46,7 +46,7 @@ * either be processing, or blocked waiting to enter the next state. There may * be up to three active txgs, and there is always a txg in the open state * (though it may be blocked waiting to enter the quiescing state). In broad - * strokes, transactions — operations that change in-memory structures — are + * strokes, transactions -- operations that change in-memory structures -- are * accepted into the txg in the open state, and are completed while the txg is * in the open or quiescing states. The accumulated changes are written to * disk in the syncing state. @@ -54,7 +54,7 @@ * Open * * When a new txg becomes active, it first enters the open state. New - * transactions — updates to in-memory structures — are assigned to the + * transactions -- updates to in-memory structures -- are assigned to the * currently open txg. There is always a txg in the open state so that ZFS can * accept new changes (though the txg may refuse new changes if it has hit * some limit). ZFS advances the open txg to the next state for a variety of @@ -375,6 +375,7 @@ txg_quiesce(dsl_pool_t *dp, uint64_t txg) ASSERT(txg == tx->tx_open_txg); tx->tx_open_txg++; + tx->tx_open_time = gethrtime(); spa_txg_history_set(dp->dp_spa, txg, TXG_STATE_OPEN, gethrtime()); spa_txg_history_add(dp->dp_spa, tx->tx_open_txg); @@ -511,7 +512,8 @@ txg_sync_thread(dsl_pool_t *dp) while (!dsl_scan_active(dp->dp_scan) && !tx->tx_exiting && timer > 0 && tx->tx_synced_txg >= tx->tx_sync_txg_waiting && - tx->tx_quiesced_txg == 0) { + tx->tx_quiesced_txg == 0 && + dp->dp_dirty_total < zfs_dirty_data_sync) { dprintf("waiting; tx_synced=%llu waiting=%llu dp=%p\n", tx->tx_synced_txg, tx->tx_sync_txg_waiting, dp); txg_thread_wait(tx, &cpr, &tx->tx_sync_more_cv, timer); @@ -574,8 +576,7 @@ txg_sync_thread(dsl_pool_t *dp) vs2->vs_bytes[ZIO_TYPE_WRITE]-vs1->vs_bytes[ZIO_TYPE_WRITE], vs2->vs_ops[ZIO_TYPE_READ]-vs1->vs_ops[ZIO_TYPE_READ], vs2->vs_ops[ZIO_TYPE_WRITE]-vs1->vs_ops[ZIO_TYPE_WRITE], - dp->dp_space_towrite[txg & TXG_MASK] + - dp->dp_tempreserved[txg & TXG_MASK] / 2); + dp->dp_dirty_pertxg[txg & TXG_MASK]); spa_txg_history_set(spa, txg, TXG_STATE_SYNCED, gethrtime()); } } @@ -705,6 +706,28 @@ txg_wait_open(dsl_pool_t *dp, uint64_t txg) mutex_exit(&tx->tx_sync_lock); } +/* + * If there isn't a txg syncing or in the pipeline, push another txg through + * the pipeline by queiscing the open txg. + */ +void +txg_kick(dsl_pool_t *dp) +{ + tx_state_t *tx = &dp->dp_tx; + + ASSERT(!dsl_pool_config_held(dp)); + + mutex_enter(&tx->tx_sync_lock); + if (tx->tx_syncing_txg == 0 && + tx->tx_quiesce_txg_waiting <= tx->tx_open_txg && + tx->tx_sync_txg_waiting <= tx->tx_synced_txg && + tx->tx_quiesced_txg <= tx->tx_synced_txg) { + tx->tx_quiesce_txg_waiting = tx->tx_open_txg + 1; + cv_broadcast(&tx->tx_quiesce_more_cv); + } + mutex_exit(&tx->tx_sync_lock); +} + boolean_t txg_stalled(dsl_pool_t *dp) { diff --git a/module/zfs/vdev.c b/module/zfs/vdev.c index ff239d72c..7751683d1 100644 --- a/module/zfs/vdev.c +++ b/module/zfs/vdev.c @@ -3296,7 +3296,7 @@ vdev_deadman(vdev_t *vd) vdev_queue_t *vq = &vd->vdev_queue; mutex_enter(&vq->vq_lock); - if (avl_numnodes(&vq->vq_pending_tree) > 0) { + if (avl_numnodes(&vq->vq_active_tree) > 0) { spa_t *spa = vd->vdev_spa; zio_t *fio; uint64_t delta; @@ -3306,7 +3306,7 @@ vdev_deadman(vdev_t *vd) * if any I/O has been outstanding for longer than * the spa_deadman_synctime we log a zevent. */ - fio = avl_first(&vq->vq_pending_tree); + fio = avl_first(&vq->vq_active_tree); delta = gethrtime() - fio->io_timestamp; if (delta > spa_deadman_synctime(spa)) { zfs_dbgmsg("SLOW IO: zio timestamp %lluns, " diff --git a/module/zfs/vdev_cache.c b/module/zfs/vdev_cache.c index 6d0cb967d..ec215ffa5 100644 --- a/module/zfs/vdev_cache.c +++ b/module/zfs/vdev_cache.c @@ -312,7 +312,7 @@ vdev_cache_read(zio_t *zio) } fio = zio_vdev_delegated_io(zio->io_vd, cache_offset, - ve->ve_data, VCBS, ZIO_TYPE_READ, ZIO_PRIORITY_CACHE_FILL, + ve->ve_data, VCBS, ZIO_TYPE_READ, ZIO_PRIORITY_NOW, ZIO_FLAG_DONT_CACHE, vdev_cache_fill, ve); ve->ve_fill_io = fio; diff --git a/module/zfs/vdev_mirror.c b/module/zfs/vdev_mirror.c index 42f7c9713..99b35f085 100644 --- a/module/zfs/vdev_mirror.c +++ b/module/zfs/vdev_mirror.c @@ -89,7 +89,7 @@ static const zio_vsd_ops_t vdev_mirror_vsd_ops = { static int vdev_mirror_pending(vdev_t *vd) { - return (avl_numnodes(&vd->vdev_queue.vq_pending_tree)); + return (avl_numnodes(&vd->vdev_queue.vq_active_tree)); } /* @@ -499,7 +499,7 @@ vdev_mirror_io_done(zio_t *zio) zio_nowait(zio_vdev_child_io(zio, zio->io_bp, mc->mc_vd, mc->mc_offset, zio->io_data, zio->io_size, - ZIO_TYPE_WRITE, zio->io_priority, + ZIO_TYPE_WRITE, ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_IO_REPAIR | (unexpected_errors ? ZIO_FLAG_SELF_HEAL : 0), NULL, NULL)); } diff --git a/module/zfs/vdev_queue.c b/module/zfs/vdev_queue.c index 06a641087..2e1f098a1 100644 --- a/module/zfs/vdev_queue.c +++ b/module/zfs/vdev_queue.c @@ -24,7 +24,7 @@ */ /* - * Copyright (c) 2012 by Delphix. All rights reserved. + * Copyright (c) 2013 by Delphix. All rights reserved. */ #include <sys/zfs_context.h> @@ -32,29 +32,134 @@ #include <sys/spa_impl.h> #include <sys/zio.h> #include <sys/avl.h> +#include <sys/dsl_pool.h> +#include <sys/spa.h> +#include <sys/spa_impl.h> #include <sys/kstat.h> /* - * These tunables are for performance analysis. + * ZFS I/O Scheduler + * --------------- + * + * ZFS issues I/O operations to leaf vdevs to satisfy and complete zios. The + * I/O scheduler determines when and in what order those operations are + * issued. The I/O scheduler divides operations into five I/O classes + * prioritized in the following order: sync read, sync write, async read, + * async write, and scrub/resilver. Each queue defines the minimum and + * maximum number of concurrent operations that may be issued to the device. + * In addition, the device has an aggregate maximum. Note that the sum of the + * per-queue minimums must not exceed the aggregate maximum. If the + * sum of the per-queue maximums exceeds the aggregate maximum, then the + * number of active i/os may reach zfs_vdev_max_active, in which case no + * further i/os will be issued regardless of whether all per-queue + * minimums have been met. + * + * For many physical devices, throughput increases with the number of + * concurrent operations, but latency typically suffers. Further, physical + * devices typically have a limit at which more concurrent operations have no + * effect on throughput or can actually cause it to decrease. + * + * The scheduler selects the next operation to issue by first looking for an + * I/O class whose minimum has not been satisfied. Once all are satisfied and + * the aggregate maximum has not been hit, the scheduler looks for classes + * whose maximum has not been satisfied. Iteration through the I/O classes is + * done in the order specified above. No further operations are issued if the + * aggregate maximum number of concurrent operations has been hit or if there + * are no operations queued for an I/O class that has not hit its maximum. + * Every time an i/o is queued or an operation completes, the I/O scheduler + * looks for new operations to issue. + * + * All I/O classes have a fixed maximum number of outstanding operations + * except for the async write class. Asynchronous writes represent the data + * that is committed to stable storage during the syncing stage for + * transaction groups (see txg.c). Transaction groups enter the syncing state + * periodically so the number of queued async writes will quickly burst up and + * then bleed down to zero. Rather than servicing them as quickly as possible, + * the I/O scheduler changes the maximum number of active async write i/os + * according to the amount of dirty data in the pool (see dsl_pool.c). Since + * both throughput and latency typically increase with the number of + * concurrent operations issued to physical devices, reducing the burstiness + * in the number of concurrent operations also stabilizes the response time of + * operations from other -- and in particular synchronous -- queues. In broad + * strokes, the I/O scheduler will issue more concurrent operations from the + * async write queue as there's more dirty data in the pool. + * + * Async Writes + * + * The number of concurrent operations issued for the async write I/O class + * follows a piece-wise linear function defined by a few adjustable points. + * + * | o---------| <-- zfs_vdev_async_write_max_active + * ^ | /^ | + * | | / | | + * active | / | | + * I/O | / | | + * count | / | | + * | / | | + * |------------o | | <-- zfs_vdev_async_write_min_active + * 0|____________^______|_________| + * 0% | | 100% of zfs_dirty_data_max + * | | + * | `-- zfs_vdev_async_write_active_max_dirty_percent + * `--------- zfs_vdev_async_write_active_min_dirty_percent + * + * Until the amount of dirty data exceeds a minimum percentage of the dirty + * data allowed in the pool, the I/O scheduler will limit the number of + * concurrent operations to the minimum. As that threshold is crossed, the + * number of concurrent operations issued increases linearly to the maximum at + * the specified maximum percentage of the dirty data allowed in the pool. + * + * Ideally, the amount of dirty data on a busy pool will stay in the sloped + * part of the function between zfs_vdev_async_write_active_min_dirty_percent + * and zfs_vdev_async_write_active_max_dirty_percent. If it exceeds the + * maximum percentage, this indicates that the rate of incoming data is + * greater than the rate that the backend storage can handle. In this case, we + * must further throttle incoming writes (see dmu_tx_delay() for details). */ -/* The maximum number of I/Os concurrently pending to each device. */ -int zfs_vdev_max_pending = 10; - /* - * The initial number of I/Os pending to each device, before it starts ramping - * up to zfs_vdev_max_pending. + * The maximum number of i/os active to each device. Ideally, this will be >= + * the sum of each queue's max_active. It must be at least the sum of each + * queue's min_active. */ -int zfs_vdev_min_pending = 4; +uint32_t zfs_vdev_max_active = 1000; /* - * The deadlines are grouped into buckets based on zfs_vdev_time_shift: - * deadline = pri + gethrtime() >> time_shift) + * Per-queue limits on the number of i/os active to each device. If the + * number of active i/os is < zfs_vdev_max_active, then the min_active comes + * into play. We will send min_active from each queue, and then select from + * queues in the order defined by zio_priority_t. + * + * In general, smaller max_active's will lead to lower latency of synchronous + * operations. Larger max_active's may lead to higher overall throughput, + * depending on underlying storage. + * + * The ratio of the queues' max_actives determines the balance of performance + * between reads, writes, and scrubs. E.g., increasing + * zfs_vdev_scrub_max_active will cause the scrub or resilver to complete + * more quickly, but reads and writes to have higher latency and lower + * throughput. */ -int zfs_vdev_time_shift = 29; /* each bucket is 0.537 seconds */ +uint32_t zfs_vdev_sync_read_min_active = 10; +uint32_t zfs_vdev_sync_read_max_active = 10; +uint32_t zfs_vdev_sync_write_min_active = 10; +uint32_t zfs_vdev_sync_write_max_active = 10; +uint32_t zfs_vdev_async_read_min_active = 1; +uint32_t zfs_vdev_async_read_max_active = 3; +uint32_t zfs_vdev_async_write_min_active = 1; +uint32_t zfs_vdev_async_write_max_active = 10; +uint32_t zfs_vdev_scrub_min_active = 1; +uint32_t zfs_vdev_scrub_max_active = 2; -/* exponential I/O issue ramp-up rate */ -int zfs_vdev_ramp_rate = 2; +/* + * When the pool has less than zfs_vdev_async_write_active_min_dirty_percent + * dirty data, use zfs_vdev_async_write_min_active. When it has more than + * zfs_vdev_async_write_active_max_dirty_percent, use + * zfs_vdev_async_write_max_active. The value is linearly interpolated + * between min and max. + */ +int zfs_vdev_async_write_active_min_dirty_percent = 30; +int zfs_vdev_async_write_active_max_dirty_percent = 60; /* * To reduce IOPs, we aggregate small adjacent I/Os into one large I/O. @@ -66,20 +171,12 @@ int zfs_vdev_aggregation_limit = SPA_MAXBLOCKSIZE; int zfs_vdev_read_gap_limit = 32 << 10; int zfs_vdev_write_gap_limit = 4 << 10; -/* - * Virtual device vector for disk I/O scheduling. - */ int -vdev_queue_deadline_compare(const void *x1, const void *x2) +vdev_queue_offset_compare(const void *x1, const void *x2) { const zio_t *z1 = x1; const zio_t *z2 = x2; - if (z1->io_deadline < z2->io_deadline) - return (-1); - if (z1->io_deadline > z2->io_deadline) - return (1); - if (z1->io_offset < z2->io_offset) return (-1); if (z1->io_offset > z2->io_offset) @@ -94,14 +191,14 @@ vdev_queue_deadline_compare(const void *x1, const void *x2) } int -vdev_queue_offset_compare(const void *x1, const void *x2) +vdev_queue_timestamp_compare(const void *x1, const void *x2) { const zio_t *z1 = x1; const zio_t *z2 = x2; - if (z1->io_offset < z2->io_offset) + if (z1->io_timestamp < z2->io_timestamp) return (-1); - if (z1->io_offset > z2->io_offset) + if (z1->io_timestamp > z2->io_timestamp) return (1); if (z1 < z2) @@ -112,25 +209,141 @@ vdev_queue_offset_compare(const void *x1, const void *x2) return (0); } +static int +vdev_queue_class_min_active(zio_priority_t p) +{ + switch (p) { + case ZIO_PRIORITY_SYNC_READ: + return (zfs_vdev_sync_read_min_active); + case ZIO_PRIORITY_SYNC_WRITE: + return (zfs_vdev_sync_write_min_active); + case ZIO_PRIORITY_ASYNC_READ: + return (zfs_vdev_async_read_min_active); + case ZIO_PRIORITY_ASYNC_WRITE: + return (zfs_vdev_async_write_min_active); + case ZIO_PRIORITY_SCRUB: + return (zfs_vdev_scrub_min_active); + default: + panic("invalid priority %u", p); + return (0); + } +} + +static int +vdev_queue_max_async_writes(uint64_t dirty) +{ + int writes; + uint64_t min_bytes = zfs_dirty_data_max * + zfs_vdev_async_write_active_min_dirty_percent / 100; + uint64_t max_bytes = zfs_dirty_data_max * + zfs_vdev_async_write_active_max_dirty_percent / 100; + + if (dirty < min_bytes) + return (zfs_vdev_async_write_min_active); + if (dirty > max_bytes) + return (zfs_vdev_async_write_max_active); + + /* + * linear interpolation: + * slope = (max_writes - min_writes) / (max_bytes - min_bytes) + * move right by min_bytes + * move up by min_writes + */ + writes = (dirty - min_bytes) * + (zfs_vdev_async_write_max_active - + zfs_vdev_async_write_min_active) / + (max_bytes - min_bytes) + + zfs_vdev_async_write_min_active; + ASSERT3U(writes, >=, zfs_vdev_async_write_min_active); + ASSERT3U(writes, <=, zfs_vdev_async_write_max_active); + return (writes); +} + +static int +vdev_queue_class_max_active(spa_t *spa, zio_priority_t p) +{ + switch (p) { + case ZIO_PRIORITY_SYNC_READ: + return (zfs_vdev_sync_read_max_active); + case ZIO_PRIORITY_SYNC_WRITE: + return (zfs_vdev_sync_write_max_active); + case ZIO_PRIORITY_ASYNC_READ: + return (zfs_vdev_async_read_max_active); + case ZIO_PRIORITY_ASYNC_WRITE: + return (vdev_queue_max_async_writes( + spa->spa_dsl_pool->dp_dirty_total)); + case ZIO_PRIORITY_SCRUB: + return (zfs_vdev_scrub_max_active); + default: + panic("invalid priority %u", p); + return (0); + } +} + +/* + * Return the i/o class to issue from, or ZIO_PRIORITY_MAX_QUEUEABLE if + * there is no eligible class. + */ +static zio_priority_t +vdev_queue_class_to_issue(vdev_queue_t *vq) +{ + spa_t *spa = vq->vq_vdev->vdev_spa; + zio_priority_t p; + + if (avl_numnodes(&vq->vq_active_tree) >= zfs_vdev_max_active) + return (ZIO_PRIORITY_NUM_QUEUEABLE); + + /* find a queue that has not reached its minimum # outstanding i/os */ + for (p = 0; p < ZIO_PRIORITY_NUM_QUEUEABLE; p++) { + if (avl_numnodes(&vq->vq_class[p].vqc_queued_tree) > 0 && + vq->vq_class[p].vqc_active < + vdev_queue_class_min_active(p)) + return (p); + } + + /* + * If we haven't found a queue, look for one that hasn't reached its + * maximum # outstanding i/os. + */ + for (p = 0; p < ZIO_PRIORITY_NUM_QUEUEABLE; p++) { + if (avl_numnodes(&vq->vq_class[p].vqc_queued_tree) > 0 && + vq->vq_class[p].vqc_active < + vdev_queue_class_max_active(spa, p)) + return (p); + } + + /* No eligible queued i/os */ + return (ZIO_PRIORITY_NUM_QUEUEABLE); +} + void vdev_queue_init(vdev_t *vd) { vdev_queue_t *vq = &vd->vdev_queue; + int max_active_sum; + zio_priority_t p; int i; mutex_init(&vq->vq_lock, NULL, MUTEX_DEFAULT, NULL); + vq->vq_vdev = vd; - avl_create(&vq->vq_deadline_tree, vdev_queue_deadline_compare, - sizeof (zio_t), offsetof(struct zio, io_deadline_node)); - - avl_create(&vq->vq_read_tree, vdev_queue_offset_compare, - sizeof (zio_t), offsetof(struct zio, io_offset_node)); - - avl_create(&vq->vq_write_tree, vdev_queue_offset_compare, - sizeof (zio_t), offsetof(struct zio, io_offset_node)); + avl_create(&vq->vq_active_tree, vdev_queue_offset_compare, + sizeof (zio_t), offsetof(struct zio, io_queue_node)); - avl_create(&vq->vq_pending_tree, vdev_queue_offset_compare, - sizeof (zio_t), offsetof(struct zio, io_offset_node)); + for (p = 0; p < ZIO_PRIORITY_NUM_QUEUEABLE; p++) { + /* + * The synchronous i/o queues are FIFO rather than LBA ordered. + * This provides more consistent latency for these i/os, and + * they tend to not be tightly clustered anyway so there is + * little to no throughput loss. + */ + boolean_t fifo = (p == ZIO_PRIORITY_SYNC_READ || + p == ZIO_PRIORITY_SYNC_WRITE); + avl_create(&vq->vq_class[p].vqc_queued_tree, + fifo ? vdev_queue_timestamp_compare : + vdev_queue_offset_compare, + sizeof (zio_t), offsetof(struct zio, io_queue_node)); + } /* * A list of buffers which can be used for aggregate I/O, this @@ -139,7 +352,10 @@ vdev_queue_init(vdev_t *vd) list_create(&vq->vq_io_list, sizeof (vdev_io_t), offsetof(vdev_io_t, vi_node)); - for (i = 0; i < zfs_vdev_max_pending; i++) + max_active_sum = zfs_vdev_sync_read_max_active + + zfs_vdev_sync_write_max_active + zfs_vdev_async_read_max_active + + zfs_vdev_async_write_max_active + zfs_vdev_scrub_max_active; + for (i = 0; i < max_active_sum; i++) list_insert_tail(&vq->vq_io_list, zio_vdev_alloc()); } @@ -148,11 +364,11 @@ vdev_queue_fini(vdev_t *vd) { vdev_queue_t *vq = &vd->vdev_queue; vdev_io_t *vi; + zio_priority_t p; - avl_destroy(&vq->vq_deadline_tree); - avl_destroy(&vq->vq_read_tree); - avl_destroy(&vq->vq_write_tree); - avl_destroy(&vq->vq_pending_tree); + for (p = 0; p < ZIO_PRIORITY_NUM_QUEUEABLE; p++) + avl_destroy(&vq->vq_class[p].vqc_queued_tree); + avl_destroy(&vq->vq_active_tree); while ((vi = list_head(&vq->vq_io_list)) != NULL) { list_remove(&vq->vq_io_list, vi); @@ -170,8 +386,8 @@ vdev_queue_io_add(vdev_queue_t *vq, zio_t *zio) spa_t *spa = zio->io_spa; spa_stats_history_t *ssh = &spa->spa_stats.io_history; - avl_add(&vq->vq_deadline_tree, zio); - avl_add(zio->io_vdev_tree, zio); + ASSERT3U(zio->io_priority, <, ZIO_PRIORITY_NUM_QUEUEABLE); + avl_add(&vq->vq_class[zio->io_priority].vqc_queued_tree, zio); if (ssh->kstat != NULL) { mutex_enter(&ssh->lock); @@ -186,8 +402,8 @@ vdev_queue_io_remove(vdev_queue_t *vq, zio_t *zio) spa_t *spa = zio->io_spa; spa_stats_history_t *ssh = &spa->spa_stats.io_history; - avl_remove(&vq->vq_deadline_tree, zio); - avl_remove(zio->io_vdev_tree, zio); + ASSERT3U(zio->io_priority, <, ZIO_PRIORITY_NUM_QUEUEABLE); + avl_remove(&vq->vq_class[zio->io_priority].vqc_queued_tree, zio); if (ssh->kstat != NULL) { mutex_enter(&ssh->lock); @@ -202,7 +418,10 @@ vdev_queue_pending_add(vdev_queue_t *vq, zio_t *zio) spa_t *spa = zio->io_spa; spa_stats_history_t *ssh = &spa->spa_stats.io_history; - avl_add(&vq->vq_pending_tree, zio); + ASSERT(MUTEX_HELD(&vq->vq_lock)); + ASSERT3U(zio->io_priority, <, ZIO_PRIORITY_NUM_QUEUEABLE); + vq->vq_class[zio->io_priority].vqc_active++; + avl_add(&vq->vq_active_tree, zio); if (ssh->kstat != NULL) { mutex_enter(&ssh->lock); @@ -217,7 +436,10 @@ vdev_queue_pending_remove(vdev_queue_t *vq, zio_t *zio) spa_t *spa = zio->io_spa; spa_stats_history_t *ssh = &spa->spa_stats.io_history; - avl_remove(&vq->vq_pending_tree, zio); + ASSERT(MUTEX_HELD(&vq->vq_lock)); + ASSERT3U(zio->io_priority, <, ZIO_PRIORITY_NUM_QUEUEABLE); + vq->vq_class[zio->io_priority].vqc_active--; + avl_remove(&vq->vq_active_tree, zio); if (ssh->kstat != NULL) { kstat_io_t *ksio = ssh->kstat->ks_data; @@ -240,12 +462,14 @@ vdev_queue_agg_io_done(zio_t *aio) { vdev_queue_t *vq = &aio->io_vd->vdev_queue; vdev_io_t *vi = aio->io_data; - zio_t *pio; - while ((pio = zio_walk_parents(aio)) != NULL) - if (aio->io_type == ZIO_TYPE_READ) + if (aio->io_type == ZIO_TYPE_READ) { + zio_t *pio; + while ((pio = zio_walk_parents(aio)) != NULL) { bcopy((char *)aio->io_data + (pio->io_offset - aio->io_offset), pio->io_data, pio->io_size); + } + } mutex_enter(&vq->vq_lock); list_insert_tail(&vq->vq_io_list, vi); @@ -262,28 +486,38 @@ vdev_queue_agg_io_done(zio_t *aio) #define IO_GAP(fio, lio) (-IO_SPAN(lio, fio)) static zio_t * -vdev_queue_io_to_issue(vdev_queue_t *vq, uint64_t pending_limit) +vdev_queue_aggregate(vdev_queue_t *vq, zio_t *zio) { - zio_t *fio, *lio, *aio, *dio, *nio, *mio; - avl_tree_t *t; vdev_io_t *vi; - int flags; - uint64_t maxspan = MIN(zfs_vdev_aggregation_limit, SPA_MAXBLOCKSIZE); - uint64_t maxgap; - int stretch; + zio_t *first, *last, *aio, *dio, *mandatory, *nio; + uint64_t maxgap = 0; + uint64_t size; + boolean_t stretch = B_FALSE; + vdev_queue_class_t *vqc = &vq->vq_class[zio->io_priority]; + avl_tree_t *t = &vqc->vqc_queued_tree; + enum zio_flag flags = zio->io_flags & ZIO_FLAG_AGG_INHERIT; + + if (zio->io_flags & ZIO_FLAG_DONT_AGGREGATE) + return (NULL); -again: - ASSERT(MUTEX_HELD(&vq->vq_lock)); + /* Prevent users from setting the zfs_vdev_aggregation_limit + * tuning larger than SPA_MAXBLOCKSIZE. */ + zfs_vdev_aggregation_limit = + MIN(zfs_vdev_aggregation_limit, SPA_MAXBLOCKSIZE); - if (avl_numnodes(&vq->vq_pending_tree) >= pending_limit || - avl_numnodes(&vq->vq_deadline_tree) == 0) + /* + * The synchronous i/o queues are not sorted by LBA, so we can't + * find adjacent i/os. These i/os tend to not be tightly clustered, + * or too large to aggregate, so this has little impact on performance. + */ + if (zio->io_priority == ZIO_PRIORITY_SYNC_READ || + zio->io_priority == ZIO_PRIORITY_SYNC_WRITE) return (NULL); - fio = lio = avl_first(&vq->vq_deadline_tree); + first = last = zio; - t = fio->io_vdev_tree; - flags = fio->io_flags & ZIO_FLAG_AGG_INHERIT; - maxgap = (t == &vq->vq_read_tree) ? zfs_vdev_read_gap_limit : 0; + if (zio->io_type == ZIO_TYPE_READ) + maxgap = zfs_vdev_read_gap_limit; vi = list_head(&vq->vq_io_list); if (vi == NULL) { @@ -291,134 +525,172 @@ again: list_insert_head(&vq->vq_io_list, vi); } - if (!(flags & ZIO_FLAG_DONT_AGGREGATE)) { - /* - * We can aggregate I/Os that are sufficiently adjacent and of - * the same flavor, as expressed by the AGG_INHERIT flags. - * The latter requirement is necessary so that certain - * attributes of the I/O, such as whether it's a normal I/O - * or a scrub/resilver, can be preserved in the aggregate. - * We can include optional I/Os, but don't allow them - * to begin a range as they add no benefit in that situation. - */ + /* + * We can aggregate I/Os that are sufficiently adjacent and of + * the same flavor, as expressed by the AGG_INHERIT flags. + * The latter requirement is necessary so that certain + * attributes of the I/O, such as whether it's a normal I/O + * or a scrub/resilver, can be preserved in the aggregate. + * We can include optional I/Os, but don't allow them + * to begin a range as they add no benefit in that situation. + */ - /* - * We keep track of the last non-optional I/O. - */ - mio = (fio->io_flags & ZIO_FLAG_OPTIONAL) ? NULL : fio; + /* + * We keep track of the last non-optional I/O. + */ + mandatory = (first->io_flags & ZIO_FLAG_OPTIONAL) ? NULL : first; - /* - * Walk backwards through sufficiently contiguous I/Os - * recording the last non-option I/O. - */ - while ((dio = AVL_PREV(t, fio)) != NULL && - (dio->io_flags & ZIO_FLAG_AGG_INHERIT) == flags && - IO_SPAN(dio, lio) <= maxspan && - IO_GAP(dio, fio) <= maxgap) { - fio = dio; - if (mio == NULL && !(fio->io_flags & ZIO_FLAG_OPTIONAL)) - mio = fio; - } + /* + * Walk backwards through sufficiently contiguous I/Os + * recording the last non-option I/O. + */ + while ((dio = AVL_PREV(t, first)) != NULL && + (dio->io_flags & ZIO_FLAG_AGG_INHERIT) == flags && + IO_SPAN(dio, last) <= zfs_vdev_aggregation_limit && + IO_GAP(dio, first) <= maxgap) { + first = dio; + if (mandatory == NULL && !(first->io_flags & ZIO_FLAG_OPTIONAL)) + mandatory = first; + } - /* - * Skip any initial optional I/Os. - */ - while ((fio->io_flags & ZIO_FLAG_OPTIONAL) && fio != lio) { - fio = AVL_NEXT(t, fio); - ASSERT(fio != NULL); - } + /* + * Skip any initial optional I/Os. + */ + while ((first->io_flags & ZIO_FLAG_OPTIONAL) && first != last) { + first = AVL_NEXT(t, first); + ASSERT(first != NULL); + } - /* - * Walk forward through sufficiently contiguous I/Os. - */ - while ((dio = AVL_NEXT(t, lio)) != NULL && - (dio->io_flags & ZIO_FLAG_AGG_INHERIT) == flags && - IO_SPAN(fio, dio) <= maxspan && - IO_GAP(lio, dio) <= maxgap) { - lio = dio; - if (!(lio->io_flags & ZIO_FLAG_OPTIONAL)) - mio = lio; - } - /* - * Now that we've established the range of the I/O aggregation - * we must decide what to do with trailing optional I/Os. - * For reads, there's nothing to do. While we are unable to - * aggregate further, it's possible that a trailing optional - * I/O would allow the underlying device to aggregate with - * subsequent I/Os. We must therefore determine if the next - * non-optional I/O is close enough to make aggregation - * worthwhile. - */ - stretch = B_FALSE; - if (t != &vq->vq_read_tree && mio != NULL) { - nio = lio; - while ((dio = AVL_NEXT(t, nio)) != NULL && - IO_GAP(nio, dio) == 0 && - IO_GAP(mio, dio) <= zfs_vdev_write_gap_limit) { - nio = dio; - if (!(nio->io_flags & ZIO_FLAG_OPTIONAL)) { - stretch = B_TRUE; - break; - } + /* + * Walk forward through sufficiently contiguous I/Os. + */ + while ((dio = AVL_NEXT(t, last)) != NULL && + (dio->io_flags & ZIO_FLAG_AGG_INHERIT) == flags && + IO_SPAN(first, dio) <= zfs_vdev_aggregation_limit && + IO_GAP(last, dio) <= maxgap) { + last = dio; + if (!(last->io_flags & ZIO_FLAG_OPTIONAL)) + mandatory = last; + } + + /* + * Now that we've established the range of the I/O aggregation + * we must decide what to do with trailing optional I/Os. + * For reads, there's nothing to do. While we are unable to + * aggregate further, it's possible that a trailing optional + * I/O would allow the underlying device to aggregate with + * subsequent I/Os. We must therefore determine if the next + * non-optional I/O is close enough to make aggregation + * worthwhile. + */ + if (zio->io_type == ZIO_TYPE_WRITE && mandatory != NULL) { + zio_t *nio = last; + while ((dio = AVL_NEXT(t, nio)) != NULL && + IO_GAP(nio, dio) == 0 && + IO_GAP(mandatory, dio) <= zfs_vdev_write_gap_limit) { + nio = dio; + if (!(nio->io_flags & ZIO_FLAG_OPTIONAL)) { + stretch = B_TRUE; + break; } } + } - if (stretch) { - /* This may be a no-op. */ - VERIFY((dio = AVL_NEXT(t, lio)) != NULL); - dio->io_flags &= ~ZIO_FLAG_OPTIONAL; - } else { - while (lio != mio && lio != fio) { - ASSERT(lio->io_flags & ZIO_FLAG_OPTIONAL); - lio = AVL_PREV(t, lio); - ASSERT(lio != NULL); - } + if (stretch) { + /* This may be a no-op. */ + dio = AVL_NEXT(t, last); + dio->io_flags &= ~ZIO_FLAG_OPTIONAL; + } else { + while (last != mandatory && last != first) { + ASSERT(last->io_flags & ZIO_FLAG_OPTIONAL); + last = AVL_PREV(t, last); + ASSERT(last != NULL); } } - if (fio != lio) { - uint64_t size = IO_SPAN(fio, lio); - ASSERT(size <= maxspan); - ASSERT(vi != NULL); - - aio = zio_vdev_delegated_io(fio->io_vd, fio->io_offset, - vi, size, fio->io_type, ZIO_PRIORITY_AGG, - flags | ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_QUEUE, - vdev_queue_agg_io_done, NULL); - aio->io_timestamp = fio->io_timestamp; - - nio = fio; - do { - dio = nio; - nio = AVL_NEXT(t, dio); - ASSERT(dio->io_type == aio->io_type); - ASSERT(dio->io_vdev_tree == t); - - if (dio->io_flags & ZIO_FLAG_NODATA) { - ASSERT(dio->io_type == ZIO_TYPE_WRITE); - bzero((char *)aio->io_data + (dio->io_offset - - aio->io_offset), dio->io_size); - } else if (dio->io_type == ZIO_TYPE_WRITE) { - bcopy(dio->io_data, (char *)aio->io_data + - (dio->io_offset - aio->io_offset), - dio->io_size); - } + if (first == last) + return (NULL); + + ASSERT(vi != NULL); + + size = IO_SPAN(first, last); + ASSERT3U(size, <=, zfs_vdev_aggregation_limit); + + aio = zio_vdev_delegated_io(first->io_vd, first->io_offset, + vi, size, first->io_type, zio->io_priority, + flags | ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_QUEUE, + vdev_queue_agg_io_done, NULL); + aio->io_timestamp = first->io_timestamp; + + nio = first; + do { + dio = nio; + nio = AVL_NEXT(t, dio); + ASSERT3U(dio->io_type, ==, aio->io_type); + + if (dio->io_flags & ZIO_FLAG_NODATA) { + ASSERT3U(dio->io_type, ==, ZIO_TYPE_WRITE); + bzero((char *)aio->io_data + (dio->io_offset - + aio->io_offset), dio->io_size); + } else if (dio->io_type == ZIO_TYPE_WRITE) { + bcopy(dio->io_data, (char *)aio->io_data + + (dio->io_offset - aio->io_offset), + dio->io_size); + } - zio_add_child(dio, aio); - vdev_queue_io_remove(vq, dio); - zio_vdev_io_bypass(dio); - zio_execute(dio); - } while (dio != lio); + zio_add_child(dio, aio); + vdev_queue_io_remove(vq, dio); + zio_vdev_io_bypass(dio); + zio_execute(dio); + } while (dio != last); - vdev_queue_pending_add(vq, aio); - list_remove(&vq->vq_io_list, vi); + list_remove(&vq->vq_io_list, vi); + + return (aio); +} + +static zio_t * +vdev_queue_io_to_issue(vdev_queue_t *vq) +{ + zio_t *zio, *aio; + zio_priority_t p; + avl_index_t idx; + vdev_queue_class_t *vqc; + zio_t *search; + +again: + ASSERT(MUTEX_HELD(&vq->vq_lock)); + + p = vdev_queue_class_to_issue(vq); - return (aio); + if (p == ZIO_PRIORITY_NUM_QUEUEABLE) { + /* No eligible queued i/os */ + return (NULL); } - ASSERT(fio->io_vdev_tree == t); - vdev_queue_io_remove(vq, fio); + /* + * For LBA-ordered queues (async / scrub), issue the i/o which follows + * the most recently issued i/o in LBA (offset) order. + * + * For FIFO queues (sync), issue the i/o with the lowest timestamp. + */ + vqc = &vq->vq_class[p]; + search = zio_buf_alloc(sizeof(*search)); + search->io_timestamp = 0; + search->io_offset = vq->vq_last_offset + 1; + VERIFY3P(avl_find(&vqc->vqc_queued_tree, search, &idx), ==, NULL); + zio_buf_free(search, sizeof(*search)); + zio = avl_nearest(&vqc->vqc_queued_tree, idx, AVL_AFTER); + if (zio == NULL) + zio = avl_first(&vqc->vqc_queued_tree); + ASSERT3U(zio->io_priority, ==, p); + + aio = vdev_queue_aggregate(vq, zio); + if (aio != NULL) + zio = aio; + else + vdev_queue_io_remove(vq, zio); /* * If the I/O is or was optional and therefore has no data, we need to @@ -426,17 +698,18 @@ again: * deadlock that we could encounter since this I/O will complete * immediately. */ - if (fio->io_flags & ZIO_FLAG_NODATA) { + if (zio->io_flags & ZIO_FLAG_NODATA) { mutex_exit(&vq->vq_lock); - zio_vdev_io_bypass(fio); - zio_execute(fio); + zio_vdev_io_bypass(zio); + zio_execute(zio); mutex_enter(&vq->vq_lock); goto again; } - vdev_queue_pending_add(vq, fio); + vdev_queue_pending_add(vq, zio); + vq->vq_last_offset = zio->io_offset; - return (fio); + return (zio); } zio_t * @@ -445,28 +718,31 @@ vdev_queue_io(zio_t *zio) vdev_queue_t *vq = &zio->io_vd->vdev_queue; zio_t *nio; - ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE); - if (zio->io_flags & ZIO_FLAG_DONT_QUEUE) return (zio); - zio->io_flags |= ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_QUEUE; + /* + * Children i/os inherent their parent's priority, which might + * not match the child's i/o type. Fix it up here. + */ + if (zio->io_type == ZIO_TYPE_READ) { + if (zio->io_priority != ZIO_PRIORITY_SYNC_READ && + zio->io_priority != ZIO_PRIORITY_ASYNC_READ && + zio->io_priority != ZIO_PRIORITY_SCRUB) + zio->io_priority = ZIO_PRIORITY_ASYNC_READ; + } else { + ASSERT(zio->io_type == ZIO_TYPE_WRITE); + if (zio->io_priority != ZIO_PRIORITY_SYNC_WRITE && + zio->io_priority != ZIO_PRIORITY_ASYNC_WRITE) + zio->io_priority = ZIO_PRIORITY_ASYNC_WRITE; + } - if (zio->io_type == ZIO_TYPE_READ) - zio->io_vdev_tree = &vq->vq_read_tree; - else - zio->io_vdev_tree = &vq->vq_write_tree; + zio->io_flags |= ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_QUEUE; mutex_enter(&vq->vq_lock); - zio->io_timestamp = gethrtime(); - zio->io_deadline = (zio->io_timestamp >> zfs_vdev_time_shift) + - zio->io_priority; - vdev_queue_io_add(vq, zio); - - nio = vdev_queue_io_to_issue(vq, zfs_vdev_min_pending); - + nio = vdev_queue_io_to_issue(vq); mutex_exit(&vq->vq_lock); if (nio == NULL) @@ -484,7 +760,7 @@ void vdev_queue_io_done(zio_t *zio) { vdev_queue_t *vq = &zio->io_vd->vdev_queue; - int i; + zio_t *nio; if (zio_injection_enabled) delay(SEC_TO_TICK(zio_handle_io_delay(zio))); @@ -497,10 +773,7 @@ vdev_queue_io_done(zio_t *zio) vq->vq_io_complete_ts = gethrtime(); vq->vq_io_delta_ts = vq->vq_io_complete_ts - zio->io_timestamp; - for (i = 0; i < zfs_vdev_ramp_rate; i++) { - zio_t *nio = vdev_queue_io_to_issue(vq, zfs_vdev_max_pending); - if (nio == NULL) - break; + while ((nio = vdev_queue_io_to_issue(vq)) != NULL) { mutex_exit(&vq->vq_lock); if (nio->io_done == vdev_queue_agg_io_done) { zio_nowait(nio); @@ -515,24 +788,61 @@ vdev_queue_io_done(zio_t *zio) } #if defined(_KERNEL) && defined(HAVE_SPL) -module_param(zfs_vdev_max_pending, int, 0644); -MODULE_PARM_DESC(zfs_vdev_max_pending, "Max pending per-vdev I/Os"); - -module_param(zfs_vdev_min_pending, int, 0644); -MODULE_PARM_DESC(zfs_vdev_min_pending, "Min pending per-vdev I/Os"); - module_param(zfs_vdev_aggregation_limit, int, 0644); MODULE_PARM_DESC(zfs_vdev_aggregation_limit, "Max vdev I/O aggregation size"); -module_param(zfs_vdev_time_shift, int, 0644); -MODULE_PARM_DESC(zfs_vdev_time_shift, "Deadline time shift for vdev I/O"); - -module_param(zfs_vdev_ramp_rate, int, 0644); -MODULE_PARM_DESC(zfs_vdev_ramp_rate, "Exponential I/O issue ramp-up rate"); - module_param(zfs_vdev_read_gap_limit, int, 0644); MODULE_PARM_DESC(zfs_vdev_read_gap_limit, "Aggregate read I/O over gap"); module_param(zfs_vdev_write_gap_limit, int, 0644); MODULE_PARM_DESC(zfs_vdev_write_gap_limit, "Aggregate write I/O over gap"); + +module_param(zfs_vdev_max_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_max_active, "Maximum number of active I/Os per vdev"); + +module_param(zfs_vdev_async_write_active_max_dirty_percent, int, 0644); +MODULE_PARM_DESC(zfs_vdev_async_write_active_max_dirty_percent, + "Async write concurrency max threshold"); + +module_param(zfs_vdev_async_write_active_min_dirty_percent, int, 0644); +MODULE_PARM_DESC(zfs_vdev_async_write_active_min_dirty_percent, + "Async write concurrency min threshold"); + +module_param(zfs_vdev_async_read_max_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_async_read_max_active, + "Max active async read I/Os per vdev"); + +module_param(zfs_vdev_async_read_min_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_async_read_min_active, + "Min active async read I/Os per vdev"); + +module_param(zfs_vdev_async_write_max_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_async_write_max_active, + "Max active async write I/Os per vdev"); + +module_param(zfs_vdev_async_write_min_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_async_write_min_active, + "Min active async write I/Os per vdev"); + +module_param(zfs_vdev_scrub_max_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_scrub_max_active, "Max active scrub I/Os per vdev"); + +module_param(zfs_vdev_scrub_min_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_scrub_min_active, "Min active scrub I/Os per vdev"); + +module_param(zfs_vdev_sync_read_max_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_sync_read_max_active, + "Max active sync read I/Os per vdev"); + +module_param(zfs_vdev_sync_read_min_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_sync_read_min_active, + "Min active sync read I/Os per vdev"); + +module_param(zfs_vdev_sync_write_max_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_sync_write_max_active, + "Max active sync write I/Os per vdev"); + +module_param(zfs_vdev_sync_write_min_active, int, 0644); +MODULE_PARM_DESC(zfs_vdev_sync_write_min_active, + "Min active sync write I/Osper vdev"); #endif diff --git a/module/zfs/vdev_raidz.c b/module/zfs/vdev_raidz.c index 9632e9af7..4cd21df89 100644 --- a/module/zfs/vdev_raidz.c +++ b/module/zfs/vdev_raidz.c @@ -2188,7 +2188,7 @@ done: zio_nowait(zio_vdev_child_io(zio, NULL, cvd, rc->rc_offset, rc->rc_data, rc->rc_size, - ZIO_TYPE_WRITE, zio->io_priority, + ZIO_TYPE_WRITE, ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_IO_REPAIR | (unexpected_errors ? ZIO_FLAG_SELF_HEAL : 0), NULL, NULL)); } diff --git a/module/zfs/zfs_fm.c b/module/zfs/zfs_fm.c index af2030ae7..df47d99cf 100644 --- a/module/zfs/zfs_fm.c +++ b/module/zfs/zfs_fm.c @@ -316,8 +316,6 @@ zfs_ereport_start(nvlist_t **ereport_out, nvlist_t **detector_out, DATA_TYPE_UINT64, zio->io_delay, NULL); fm_payload_set(ereport, FM_EREPORT_PAYLOAD_ZFS_ZIO_TIMESTAMP, DATA_TYPE_UINT64, zio->io_timestamp, NULL); - fm_payload_set(ereport, FM_EREPORT_PAYLOAD_ZFS_ZIO_DEADLINE, - DATA_TYPE_UINT64, zio->io_deadline, NULL); fm_payload_set(ereport, FM_EREPORT_PAYLOAD_ZFS_ZIO_DELTA, DATA_TYPE_UINT64, zio->io_delta, NULL); diff --git a/module/zfs/zfs_vnops.c b/module/zfs/zfs_vnops.c index 1552b61e0..6f25a6fff 100644 --- a/module/zfs/zfs_vnops.c +++ b/module/zfs/zfs_vnops.c @@ -125,7 +125,11 @@ * forever, because the previous txg can't quiesce until B's tx commits. * * If dmu_tx_assign() returns ERESTART and zsb->z_assign is TXG_NOWAIT, - * then drop all locks, call dmu_tx_wait(), and try again. + * then drop all locks, call dmu_tx_wait(), and try again. On subsequent + * calls to dmu_tx_assign(), pass TXG_WAITED rather than TXG_NOWAIT, + * to indicate that this operation has already called dmu_tx_wait(). + * This will ensure that we don't retry forever, waiting a short bit + * each time. * * (5) If the operation succeeded, generate the intent log entry for it * before dropping locks. This ensures that the ordering of events @@ -147,12 +151,13 @@ * rw_enter(...); // grab any other locks you need * tx = dmu_tx_create(...); // get DMU tx * dmu_tx_hold_*(); // hold each object you might modify - * error = dmu_tx_assign(tx, TXG_NOWAIT); // try to assign + * error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); * if (error) { * rw_exit(...); // drop locks * zfs_dirent_unlock(dl); // unlock directory entry * iput(...); // release held vnodes * if (error == ERESTART) { + * waited = B_TRUE; * dmu_tx_wait(tx); * dmu_tx_abort(tx); * goto top; @@ -1279,6 +1284,7 @@ zfs_create(struct inode *dip, char *name, vattr_t *vap, int excl, zfs_acl_ids_t acl_ids; boolean_t fuid_dirtied; boolean_t have_acl = B_FALSE; + boolean_t waited = B_FALSE; /* * If we have an ephemeral id, ACL, or XVATTR then @@ -1391,10 +1397,11 @@ top: dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, acl_ids.z_aclp->z_acl_bytes); } - error = dmu_tx_assign(tx, TXG_NOWAIT); + error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); if (error) { zfs_dirent_unlock(dl); if (error == ERESTART) { + waited = B_TRUE; dmu_tx_wait(tx); dmu_tx_abort(tx); goto top; @@ -1524,6 +1531,7 @@ zfs_remove(struct inode *dip, char *name, cred_t *cr) #endif /* HAVE_PN_UTILS */ int error; int zflg = ZEXISTS; + boolean_t waited = B_FALSE; ZFS_ENTER(zsb); ZFS_VERIFY_ZP(dzp); @@ -1599,13 +1607,14 @@ top: /* charge as an update -- would be nice not to charge at all */ dmu_tx_hold_zap(tx, zsb->z_unlinkedobj, FALSE, NULL); - error = dmu_tx_assign(tx, TXG_NOWAIT); + error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); if (error) { zfs_dirent_unlock(dl); iput(ip); if (xzp) iput(ZTOI(xzp)); if (error == ERESTART) { + waited = B_TRUE; dmu_tx_wait(tx); dmu_tx_abort(tx); goto top; @@ -1710,6 +1719,7 @@ zfs_mkdir(struct inode *dip, char *dirname, vattr_t *vap, struct inode **ipp, gid_t gid = crgetgid(cr); zfs_acl_ids_t acl_ids; boolean_t fuid_dirtied; + boolean_t waited = B_FALSE; ASSERT(S_ISDIR(vap->va_mode)); @@ -1801,10 +1811,11 @@ top: dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes + ZFS_SA_BASE_ATTR_SIZE); - error = dmu_tx_assign(tx, TXG_NOWAIT); + error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); if (error) { zfs_dirent_unlock(dl); if (error == ERESTART) { + waited = B_TRUE; dmu_tx_wait(tx); dmu_tx_abort(tx); goto top; @@ -1882,6 +1893,7 @@ zfs_rmdir(struct inode *dip, char *name, struct inode *cwd, cred_t *cr, dmu_tx_t *tx; int error; int zflg = ZEXISTS; + boolean_t waited = B_FALSE; ZFS_ENTER(zsb); ZFS_VERIFY_ZP(dzp); @@ -1935,13 +1947,14 @@ top: dmu_tx_hold_zap(tx, zsb->z_unlinkedobj, FALSE, NULL); zfs_sa_upgrade_txholds(tx, zp); zfs_sa_upgrade_txholds(tx, dzp); - error = dmu_tx_assign(tx, TXG_NOWAIT); + error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); if (error) { rw_exit(&zp->z_parent_lock); rw_exit(&zp->z_name_lock); zfs_dirent_unlock(dl); iput(ip); if (error == ERESTART) { + waited = B_TRUE; dmu_tx_wait(tx); dmu_tx_abort(tx); goto top; @@ -3169,6 +3182,7 @@ zfs_rename(struct inode *sdip, char *snm, struct inode *tdip, char *tnm, int cmp, serr, terr; int error = 0; int zflg = 0; + boolean_t waited = B_FALSE; ZFS_ENTER(zsb); ZFS_VERIFY_ZP(sdzp); @@ -3383,7 +3397,7 @@ top: zfs_sa_upgrade_txholds(tx, szp); dmu_tx_hold_zap(tx, zsb->z_unlinkedobj, FALSE, NULL); - error = dmu_tx_assign(tx, TXG_NOWAIT); + error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); if (error) { if (zl != NULL) zfs_rename_unlock(&zl); @@ -3397,6 +3411,7 @@ top: if (tzp) iput(ZTOI(tzp)); if (error == ERESTART) { + waited = B_TRUE; dmu_tx_wait(tx); dmu_tx_abort(tx); goto top; @@ -3504,6 +3519,7 @@ zfs_symlink(struct inode *dip, char *name, vattr_t *vap, char *link, zfs_acl_ids_t acl_ids; boolean_t fuid_dirtied; uint64_t txtype = TX_SYMLINK; + boolean_t waited = B_FALSE; ASSERT(S_ISLNK(vap->va_mode)); @@ -3568,10 +3584,11 @@ top: } if (fuid_dirtied) zfs_fuid_txhold(zsb, tx); - error = dmu_tx_assign(tx, TXG_NOWAIT); + error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); if (error) { zfs_dirent_unlock(dl); if (error == ERESTART) { + waited = B_TRUE; dmu_tx_wait(tx); dmu_tx_abort(tx); goto top; @@ -3699,6 +3716,7 @@ zfs_link(struct inode *tdip, struct inode *sip, char *name, cred_t *cr) int zf = ZNEW; uint64_t parent; uid_t owner; + boolean_t waited = B_FALSE; ASSERT(S_ISDIR(tdip->i_mode)); @@ -3782,10 +3800,11 @@ top: dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); zfs_sa_upgrade_txholds(tx, szp); zfs_sa_upgrade_txholds(tx, dzp); - error = dmu_tx_assign(tx, TXG_NOWAIT); + error = dmu_tx_assign(tx, waited ? TXG_WAITED : TXG_NOWAIT); if (error) { zfs_dirent_unlock(dl); if (error == ERESTART) { + waited = B_TRUE; dmu_tx_wait(tx); dmu_tx_abort(tx); goto top; diff --git a/module/zfs/zil.c b/module/zfs/zil.c index 839afa956..30035faa0 100644 --- a/module/zfs/zil.c +++ b/module/zfs/zil.c @@ -913,7 +913,7 @@ zil_lwb_write_init(zilog_t *zilog, lwb_t *lwb) } lwb->lwb_zio = zio_rewrite(zilog->zl_root_zio, zilog->zl_spa, 0, &lwb->lwb_blk, lwb->lwb_buf, BP_GET_LSIZE(&lwb->lwb_blk), - zil_lwb_write_done, lwb, ZIO_PRIORITY_LOG_WRITE, + zil_lwb_write_done, lwb, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_FASTWRITE, &zb); } diff --git a/module/zfs/zio.c b/module/zfs/zio.c index bc9d5b920..7cc3d4c9a 100644 --- a/module/zfs/zio.c +++ b/module/zfs/zio.c @@ -39,30 +39,10 @@ /* * ========================================================================== - * I/O priority table - * ========================================================================== - */ -uint8_t zio_priority_table[ZIO_PRIORITY_TABLE_SIZE] = { - 0, /* ZIO_PRIORITY_NOW */ - 0, /* ZIO_PRIORITY_SYNC_READ */ - 0, /* ZIO_PRIORITY_SYNC_WRITE */ - 0, /* ZIO_PRIORITY_LOG_WRITE */ - 1, /* ZIO_PRIORITY_CACHE_FILL */ - 1, /* ZIO_PRIORITY_AGG */ - 4, /* ZIO_PRIORITY_FREE */ - 4, /* ZIO_PRIORITY_ASYNC_WRITE */ - 6, /* ZIO_PRIORITY_ASYNC_READ */ - 10, /* ZIO_PRIORITY_RESILVER */ - 20, /* ZIO_PRIORITY_SCRUB */ - 2, /* ZIO_PRIORITY_DDT_PREFETCH */ -}; - -/* - * ========================================================================== * I/O type descriptions * ========================================================================== */ -char *zio_type_name[ZIO_TYPES] = { +const char *zio_type_name[ZIO_TYPES] = { "z_null", "z_rd", "z_wr", "z_fr", "z_cl", "z_ioctl" }; @@ -549,7 +529,10 @@ zio_notify_parent(zio_t *pio, zio_t *zio, enum zio_wait_type wait) *errorp = zio_worst_error(*errorp, zio->io_error); pio->io_reexecute |= zio->io_reexecute; ASSERT3U(*countp, >, 0); - if (--*countp == 0 && pio->io_stall == countp) { + + (*countp)--; + + if (*countp == 0 && pio->io_stall == countp) { pio->io_stall = NULL; mutex_exit(&pio->io_lock); __zio_execute(pio); @@ -573,7 +556,7 @@ zio_inherit_child_errors(zio_t *zio, enum zio_child c) static zio_t * zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, void *data, uint64_t size, zio_done_func_t *done, void *private, - zio_type_t type, int priority, enum zio_flag flags, + zio_type_t type, zio_priority_t priority, enum zio_flag flags, vdev_t *vd, uint64_t offset, const zbookmark_t *zb, enum zio_stage stage, enum zio_stage pipeline) { @@ -620,6 +603,7 @@ zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, zio->io_spa = spa; zio->io_txg = txg; zio->io_ready = NULL; + zio->io_physdone = NULL; zio->io_done = done; zio->io_private = private; zio->io_prev_space_delta = 0; @@ -629,7 +613,6 @@ zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, zio->io_vsd = NULL; zio->io_vsd_ops = NULL; zio->io_offset = offset; - zio->io_deadline = 0; zio->io_timestamp = 0; zio->io_delta = 0; zio->io_delay = 0; @@ -646,6 +629,7 @@ zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, zio->io_transform_stack = NULL; zio->io_error = 0; zio->io_child_count = 0; + zio->io_phys_children = 0; zio->io_parent_count = 0; zio->io_stall = NULL; zio->io_gang_leader = NULL; @@ -706,7 +690,7 @@ zio_root(spa_t *spa, zio_done_func_t *done, void *private, enum zio_flag flags) zio_t * zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data, uint64_t size, zio_done_func_t *done, void *private, - int priority, enum zio_flag flags, const zbookmark_t *zb) + zio_priority_t priority, enum zio_flag flags, const zbookmark_t *zb) { zio_t *zio; @@ -722,8 +706,9 @@ zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, zio_t * zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, void *data, uint64_t size, const zio_prop_t *zp, - zio_done_func_t *ready, zio_done_func_t *done, void *private, - int priority, enum zio_flag flags, const zbookmark_t *zb) + zio_done_func_t *ready, zio_done_func_t *physdone, zio_done_func_t *done, + void *private, + zio_priority_t priority, enum zio_flag flags, const zbookmark_t *zb) { zio_t *zio; @@ -742,6 +727,7 @@ zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, ZIO_DDT_CHILD_WRITE_PIPELINE : ZIO_WRITE_PIPELINE); zio->io_ready = ready; + zio->io_physdone = physdone; zio->io_prop = *zp; return (zio); @@ -749,8 +735,8 @@ zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, zio_t * zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, void *data, - uint64_t size, zio_done_func_t *done, void *private, int priority, - enum zio_flag flags, zbookmark_t *zb) + uint64_t size, zio_done_func_t *done, void *private, + zio_priority_t priority, enum zio_flag flags, zbookmark_t *zb) { zio_t *zio; @@ -829,7 +815,6 @@ zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, NULL, NULL, ZIO_TYPE_FREE, ZIO_PRIORITY_NOW, flags, NULL, 0, NULL, ZIO_STAGE_OPEN, stage); - return (zio); } @@ -864,14 +849,14 @@ zio_claim(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, zio_t * zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd, - zio_done_func_t *done, void *private, int priority, enum zio_flag flags) + zio_done_func_t *done, void *private, enum zio_flag flags) { zio_t *zio; int c; if (vd->vdev_children == 0) { zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private, - ZIO_TYPE_IOCTL, priority, flags, vd, 0, NULL, + ZIO_TYPE_IOCTL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL, ZIO_STAGE_OPEN, ZIO_IOCTL_PIPELINE); zio->io_cmd = cmd; @@ -880,7 +865,7 @@ zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd, for (c = 0; c < vd->vdev_children; c++) zio_nowait(zio_ioctl(zio, spa, vd->vdev_child[c], cmd, - done, private, priority, flags)); + done, private, flags)); } return (zio); @@ -889,7 +874,7 @@ zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd, zio_t * zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, void *data, int checksum, zio_done_func_t *done, void *private, - int priority, enum zio_flag flags, boolean_t labels) + zio_priority_t priority, enum zio_flag flags, boolean_t labels) { zio_t *zio; @@ -910,7 +895,7 @@ zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, zio_t * zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, void *data, int checksum, zio_done_func_t *done, void *private, - int priority, enum zio_flag flags, boolean_t labels) + zio_priority_t priority, enum zio_flag flags, boolean_t labels) { zio_t *zio; @@ -945,8 +930,8 @@ zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, */ zio_t * zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset, - void *data, uint64_t size, int type, int priority, enum zio_flag flags, - zio_done_func_t *done, void *private) + void *data, uint64_t size, int type, zio_priority_t priority, + enum zio_flag flags, zio_done_func_t *done, void *private) { enum zio_stage pipeline = ZIO_VDEV_CHILD_PIPELINE; zio_t *zio; @@ -981,12 +966,16 @@ zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset, done, private, type, priority, flags, vd, offset, &pio->io_bookmark, ZIO_STAGE_VDEV_IO_START >> 1, pipeline); + zio->io_physdone = pio->io_physdone; + if (vd->vdev_ops->vdev_op_leaf && zio->io_logical != NULL) + zio->io_logical->io_phys_children++; + return (zio); } zio_t * zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, void *data, uint64_t size, - int type, int priority, enum zio_flag flags, + int type, zio_priority_t priority, enum zio_flag flags, zio_done_func_t *done, void *private) { zio_t *zio; @@ -995,7 +984,7 @@ zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, void *data, uint64_t size, zio = zio_create(NULL, vd->vdev_spa, 0, NULL, data, size, done, private, type, priority, - flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY, + flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY | ZIO_FLAG_DELEGATED, vd, offset, NULL, ZIO_STAGE_VDEV_IO_START >> 1, ZIO_VDEV_CHILD_PIPELINE); @@ -1006,7 +995,7 @@ void zio_flush(zio_t *zio, vdev_t *vd) { zio_nowait(zio_ioctl(zio, zio->io_spa, vd, DKIOCFLUSHWRITECACHE, - NULL, NULL, ZIO_PRIORITY_NOW, + NULL, NULL, ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_DONT_RETRY)); } @@ -1951,7 +1940,7 @@ zio_write_gang_block(zio_t *pio) zio_nowait(zio_write(zio, spa, txg, &gbh->zg_blkptr[g], (char *)pio->io_data + (pio->io_size - resid), lsize, &zp, - zio_write_gang_member_ready, NULL, &gn->gn_child[g], + zio_write_gang_member_ready, NULL, NULL, &gn->gn_child[g], pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark)); } @@ -2335,7 +2324,7 @@ zio_ddt_write(zio_t *zio) } dio = zio_write(zio, spa, txg, bp, zio->io_orig_data, - zio->io_orig_size, &czp, NULL, + zio->io_orig_size, &czp, NULL, NULL, zio_ddt_ditto_write_done, dde, zio->io_priority, ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark); @@ -2357,7 +2346,7 @@ zio_ddt_write(zio_t *zio) ddt_phys_addref(ddp); } else { cio = zio_write(zio, spa, txg, bp, zio->io_orig_data, - zio->io_orig_size, zp, zio_ddt_child_write_ready, + zio->io_orig_size, zp, zio_ddt_child_write_ready, NULL, zio_ddt_child_write_done, dde, zio->io_priority, ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark); @@ -2780,6 +2769,13 @@ zio_vdev_io_assess(zio_t *zio) if (zio->io_error) zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; + if (vd != NULL && vd->vdev_ops->vdev_op_leaf && + zio->io_physdone != NULL) { + ASSERT(!(zio->io_flags & ZIO_FLAG_DELEGATED)); + ASSERT(zio->io_child_type == ZIO_CHILD_VDEV); + zio->io_physdone(zio->io_logical); + } + return (ZIO_PIPELINE_CONTINUE); } @@ -3346,7 +3342,6 @@ EXPORT_SYMBOL(zio_clear_fault); EXPORT_SYMBOL(zio_handle_fault_injection); EXPORT_SYMBOL(zio_handle_device_injection); EXPORT_SYMBOL(zio_handle_label_injection); -EXPORT_SYMBOL(zio_priority_table); EXPORT_SYMBOL(zio_type_name); module_param(zio_bulk_flags, int, 0644); |