diff options
| -rw-r--r-- | include/sys/arc.h | 2 | ||||
| -rw-r--r-- | include/sys/spa.h | 1 | ||||
| -rw-r--r-- | include/sys/spa_impl.h | 5 | ||||
| -rw-r--r-- | module/zfs/arc.c | 51 | ||||
| -rw-r--r-- | module/zfs/dsl_dir.c | 2 | ||||
| -rw-r--r-- | module/zfs/spa_misc.c | 6 |
6 files changed, 50 insertions, 17 deletions
diff --git a/include/sys/arc.h b/include/sys/arc.h index 9d6bab505..a5bdefb56 100644 --- a/include/sys/arc.h +++ b/include/sys/arc.h @@ -289,7 +289,7 @@ void arc_freed(spa_t *spa, const blkptr_t *bp); void arc_flush(spa_t *spa, boolean_t retry); void arc_tempreserve_clear(uint64_t reserve); -int arc_tempreserve_space(uint64_t reserve, uint64_t txg); +int arc_tempreserve_space(spa_t *spa, uint64_t reserve, uint64_t txg); uint64_t arc_target_bytes(void); void arc_init(void); diff --git a/include/sys/spa.h b/include/sys/spa.h index 4a3fc71f7..82fe2c18c 100644 --- a/include/sys/spa.h +++ b/include/sys/spa.h @@ -990,6 +990,7 @@ extern uint64_t spa_delegation(spa_t *spa); extern objset_t *spa_meta_objset(spa_t *spa); extern uint64_t spa_deadman_synctime(spa_t *spa); extern uint64_t spa_deadman_ziotime(spa_t *spa); +extern uint64_t spa_dirty_data(spa_t *spa); /* Miscellaneous support routines */ extern void spa_load_failed(spa_t *spa, const char *fmt, ...); diff --git a/include/sys/spa_impl.h b/include/sys/spa_impl.h index 8d2a31961..8d2a20dbb 100644 --- a/include/sys/spa_impl.h +++ b/include/sys/spa_impl.h @@ -363,6 +363,11 @@ struct spa { uint64_t spa_errata; /* errata issues detected */ spa_stats_t spa_stats; /* assorted spa statistics */ spa_keystore_t spa_keystore; /* loaded crypto keys */ + + /* arc_memory_throttle() parameters during low memory condition */ + uint64_t spa_lowmem_page_load; /* memory load during txg */ + uint64_t spa_lowmem_last_txg; /* txg window start */ + hrtime_t spa_ccw_fail_time; /* Conf cache write fail time */ taskq_t *spa_zvol_taskq; /* Taskq for minor management */ taskq_t *spa_prefetch_taskq; /* Taskq for prefetch threads */ diff --git a/module/zfs/arc.c b/module/zfs/arc.c index e49f8a547..7f2929c17 100644 --- a/module/zfs/arc.c +++ b/module/zfs/arc.c @@ -392,6 +392,16 @@ int zfs_arc_shrink_shift = 0; int zfs_arc_p_min_shift = 0; int zfs_arc_average_blocksize = 8 * 1024; /* 8KB */ +/* + * ARC dirty data constraints for arc_tempreserve_space() throttle. + */ +unsigned long zfs_arc_dirty_limit_percent = 50; /* total dirty data limit */ +unsigned long zfs_arc_anon_limit_percent = 25; /* anon block dirty limit */ +unsigned long zfs_arc_pool_dirty_percent = 20; /* each pool's anon allowance */ + +/* + * Enable or disable compressed arc buffers. + */ int zfs_compressed_arc_enabled = B_TRUE; /* @@ -7182,12 +7192,10 @@ arc_write(zio_t *pio, spa_t *spa, uint64_t txg, } static int -arc_memory_throttle(uint64_t reserve, uint64_t txg) +arc_memory_throttle(spa_t *spa, uint64_t reserve, uint64_t txg) { #ifdef _KERNEL uint64_t available_memory = arc_free_memory(); - static uint64_t page_load = 0; - static uint64_t last_txg = 0; #if defined(_ILP32) available_memory = @@ -7197,9 +7205,9 @@ arc_memory_throttle(uint64_t reserve, uint64_t txg) if (available_memory > arc_all_memory() * arc_lotsfree_percent / 100) return (0); - if (txg > last_txg) { - last_txg = txg; - page_load = 0; + if (txg > spa->spa_lowmem_last_txg) { + spa->spa_lowmem_last_txg = txg; + spa->spa_lowmem_page_load = 0; } /* * If we are in pageout, we know that memory is already tight, @@ -7207,21 +7215,22 @@ arc_memory_throttle(uint64_t reserve, uint64_t txg) * continue to let page writes occur as quickly as possible. */ if (current_is_kswapd()) { - if (page_load > MAX(arc_sys_free / 4, available_memory) / 4) { + if (spa->spa_lowmem_page_load > + MAX(arc_sys_free / 4, available_memory) / 4) { DMU_TX_STAT_BUMP(dmu_tx_memory_reclaim); return (SET_ERROR(ERESTART)); } /* Note: reserve is inflated, so we deflate */ - page_load += reserve / 8; + atomic_add_64(&spa->spa_lowmem_page_load, reserve / 8); return (0); - } else if (page_load > 0 && arc_reclaim_needed()) { + } else if (spa->spa_lowmem_page_load > 0 && arc_reclaim_needed()) { /* memory is low, delay before restarting */ ARCSTAT_INCR(arcstat_memory_throttle_count, 1); DMU_TX_STAT_BUMP(dmu_tx_memory_reclaim); return (SET_ERROR(EAGAIN)); } - page_load = 0; -#endif + spa->spa_lowmem_page_load = 0; +#endif /* _KERNEL */ return (0); } @@ -7233,7 +7242,7 @@ arc_tempreserve_clear(uint64_t reserve) } int -arc_tempreserve_space(uint64_t reserve, uint64_t txg) +arc_tempreserve_space(spa_t *spa, uint64_t reserve, uint64_t txg) { int error; uint64_t anon_size; @@ -7269,7 +7278,7 @@ 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. */ - error = arc_memory_throttle(reserve, txg); + error = arc_memory_throttle(spa, reserve, txg); if (error != 0) return (error); @@ -7277,12 +7286,24 @@ arc_tempreserve_space(uint64_t reserve, uint64_t txg) * Throttle writes when the amount of dirty data in the cache * gets too large. We try to keep the cache less than half full * of dirty blocks so that our sync times don't grow too large. + * + * In the case of one pool being built on another pool, we want + * to make sure we don't end up throttling the lower (backing) + * pool when the upper pool is the majority contributor to dirty + * data. To insure we make forward progress during throttling, we + * also check the current pool's net dirty data and only throttle + * if it exceeds zfs_arc_pool_dirty_percent of the anonymous dirty + * data in the cache. + * * Note: if two requests come in concurrently, we might let them * both succeed, when one of them should fail. Not a huge deal. */ + uint64_t total_dirty = reserve + arc_tempreserve + anon_size; + uint64_t spa_dirty_anon = spa_dirty_data(spa); - if (reserve + arc_tempreserve + anon_size > arc_c / 2 && - anon_size > arc_c / 4) { + if (total_dirty > arc_c * zfs_arc_dirty_limit_percent / 100 && + anon_size > arc_c * zfs_arc_anon_limit_percent / 100 && + spa_dirty_anon > anon_size * zfs_arc_pool_dirty_percent / 100) { #ifdef ZFS_DEBUG uint64_t meta_esize = refcount_count(&arc_anon->arcs_esize[ARC_BUFC_METADATA]); diff --git a/module/zfs/dsl_dir.c b/module/zfs/dsl_dir.c index 75c40c68c..9a43691e5 100644 --- a/module/zfs/dsl_dir.c +++ b/module/zfs/dsl_dir.c @@ -1416,7 +1416,7 @@ dsl_dir_tempreserve_space(dsl_dir_t *dd, uint64_t lsize, uint64_t asize, offsetof(struct tempreserve, tr_node)); ASSERT3S(asize, >, 0); - err = arc_tempreserve_space(lsize, tx->tx_txg); + err = arc_tempreserve_space(dd->dd_pool->dp_spa, lsize, tx->tx_txg); if (err == 0) { struct tempreserve *tr; diff --git a/module/zfs/spa_misc.c b/module/zfs/spa_misc.c index 9410fab07..f43a38ef1 100644 --- a/module/zfs/spa_misc.c +++ b/module/zfs/spa_misc.c @@ -1917,6 +1917,12 @@ bp_get_dsize(spa_t *spa, const blkptr_t *bp) return (dsize); } +uint64_t +spa_dirty_data(spa_t *spa) +{ + return (spa->spa_dsl_pool->dp_dirty_total); +} + /* * ========================================================================== * Initialization and Termination |