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author | mav <mav@FreeBSD.org> | 2015-02-03 08:06:13 +0000 |
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committer | mav <mav@FreeBSD.org> | 2015-02-03 08:06:13 +0000 |
commit | 683ce518a8bf980a59801ed2b33474929b01cd19 (patch) | |
tree | c02e46c522a3f92959092fb2ea5d905291b9d57a /sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c | |
parent | d98d4221cea35503f6cfc838cc7741d8aa49b3a1 (diff) | |
download | FreeBSD-src-683ce518a8bf980a59801ed2b33474929b01cd19.zip FreeBSD-src-683ce518a8bf980a59801ed2b33474929b01cd19.tar.gz |
MFC r277419:
Allow skipping dmu_buf_will_dirty() call in dsl_dir_transfer_space().
dsl_dir_transfer_space() is mostly called after dsl_dir_diduse_space(),
which already calls dmu_buf_will_dirty() for the same dbuf and tx, so
its duplicate call in those cases will change nothing, only spend time.
Skipping this call by four times reduces time spent in dbuf_write_done()
and descendants, updating dataset statistics with several congested lock
acquisitions. When rewriting 8K zvol blocks at 1GB/s rate, this reduces
CPU time spent inside dbuf_write_done(), according to profiling, from 45%
of 683K samples to 18% of 422K.
Diffstat (limited to 'sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c')
-rw-r--r-- | sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c index 5a891d1b..1862f8c 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c @@ -1389,7 +1389,7 @@ dsl_dir_diduse_space(dsl_dir_t *dd, dd_used_t type, accounted_delta, compressed, uncompressed, tx); dsl_dir_transfer_space(dd->dd_parent, used - accounted_delta, - DD_USED_CHILD_RSRV, DD_USED_CHILD, tx); + DD_USED_CHILD_RSRV, DD_USED_CHILD, NULL); } } @@ -1397,7 +1397,7 @@ void dsl_dir_transfer_space(dsl_dir_t *dd, int64_t delta, dd_used_t oldtype, dd_used_t newtype, dmu_tx_t *tx) { - ASSERT(dmu_tx_is_syncing(tx)); + ASSERT(tx == NULL || dmu_tx_is_syncing(tx)); ASSERT(oldtype < DD_USED_NUM); ASSERT(newtype < DD_USED_NUM); @@ -1405,7 +1405,8 @@ dsl_dir_transfer_space(dsl_dir_t *dd, int64_t delta, !(dsl_dir_phys(dd)->dd_flags & DD_FLAG_USED_BREAKDOWN)) return; - dmu_buf_will_dirty(dd->dd_dbuf, tx); + if (tx != NULL) + dmu_buf_will_dirty(dd->dd_dbuf, tx); mutex_enter(&dd->dd_lock); ASSERT(delta > 0 ? dsl_dir_phys(dd)->dd_used_breakdown[oldtype] >= delta : |