diff options
| author | George Wilson <[email protected]> | 2013-05-06 10:14:52 -0700 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2013-05-06 12:39:34 -0700 |
| commit | 55d85d5a8c45c4559a4a0e675c37b0c3afb19c2f (patch) | |
| tree | de4e1e0564aa00bb1dcb8b91c15e9655f7f36248 /module/zfs/zio.c | |
| parent | 5853fe790d1df58c5dd85ea52c5e165b6d43013c (diff) | |
Illumos #3329, #3330, #3331, #3335
3329 spa_sync() spends 10-20% of its time in spa_free_sync_cb()
3330 space_seg_t should have its own kmem_cache
3331 deferred frees should happen after sync_pass 1
3335 make SYNC_PASS_* constants tunable
Reviewed by: Adam Leventhal <[email protected]>
Reviewed by: Matt Ahrens <[email protected]>
Reviewed by: Christopher Siden <[email protected]>
Reviewed by: Eric Schrock <[email protected]>
Reviewed by: Richard Lowe <[email protected]>
Reviewed by: Dan McDonald <[email protected]>
Approved by: Eric Schrock <[email protected]>
References:
illumos/illumos-gate@01f55e48fb4d524eaf70687728aa51b7762e2e97
https://www.illumos.org/issues/3329
https://www.illumos.org/issues/3330
https://www.illumos.org/issues/3331
https://www.illumos.org/issues/3335
Ported-by: Brian Behlendorf <[email protected]>
Diffstat (limited to 'module/zfs/zio.c')
| -rw-r--r-- | module/zfs/zio.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/module/zfs/zio.c b/module/zfs/zio.c index a721903a3..fda76123e 100644 --- a/module/zfs/zio.c +++ b/module/zfs/zio.c @@ -85,6 +85,22 @@ extern vmem_t *zio_alloc_arena; extern int zfs_mg_alloc_failures; /* + * The following actions directly effect the spa's sync-to-convergence logic. + * The values below define the sync pass when we start performing the action. + * Care should be taken when changing these values as they directly impact + * spa_sync() performance. Tuning these values may introduce subtle performance + * pathologies and should only be done in the context of performance analysis. + * These tunables will eventually be removed and replaced with #defines once + * enough analysis has been done to determine optimal values. + * + * The 'zfs_sync_pass_deferred_free' pass must be greater than 1 to ensure that + * regular blocks are not deferred. + */ +int zfs_sync_pass_deferred_free = 2; /* defer frees starting in this pass */ +int zfs_sync_pass_dont_compress = 5; /* don't compress starting in this pass */ +int zfs_sync_pass_rewrite = 2; /* rewrite new bps starting in this pass */ + +/* * An allocating zio is one that either currently has the DVA allocate * stage set or will have it later in its lifetime. */ @@ -771,7 +787,7 @@ zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, ASSERT(!BP_IS_HOLE(bp)); ASSERT(spa_syncing_txg(spa) == txg); - ASSERT(spa_sync_pass(spa) <= SYNC_PASS_DEFERRED_FREE); + ASSERT(spa_sync_pass(spa) < zfs_sync_pass_deferred_free); zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp), NULL, NULL, ZIO_TYPE_FREE, ZIO_PRIORITY_FREE, flags, @@ -1068,7 +1084,7 @@ zio_write_bp_init(zio_t *zio) ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); ASSERT(!BP_GET_DEDUP(bp)); - if (pass > SYNC_PASS_DONT_COMPRESS) + if (pass >= zfs_sync_pass_dont_compress) compress = ZIO_COMPRESS_OFF; /* Make sure someone doesn't change their mind on overwrites */ @@ -1097,7 +1113,7 @@ zio_write_bp_init(zio_t *zio) * There should only be a handful of blocks after pass 1 in any case. */ if (bp->blk_birth == zio->io_txg && BP_GET_PSIZE(bp) == psize && - pass > SYNC_PASS_REWRITE) { + pass >= zfs_sync_pass_rewrite) { enum zio_stage gang_stages = zio->io_pipeline & ZIO_GANG_STAGES; ASSERT(psize != 0); zio->io_pipeline = ZIO_REWRITE_PIPELINE | gang_stages; |