Date: Wed, 3 Oct 2018 15:35:27 +0000 (UTC) From: Alexander Motin <mav@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r339152 - stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs Message-ID: <201810031535.w93FZR7e056647@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: mav Date: Wed Oct 3 15:35:27 2018 New Revision: 339152 URL: https://svnweb.freebsd.org/changeset/base/339152 Log: MFC r337972: 9751 Allocation throttling misplacing ditto blocks Relax allocation throttling for ditto blocks. Due to random imbalances in allocation it tends to push block copies to one vdev, that looks slightly better at the moment. Slightly less strict policy allows both improve data security and surprisingly write performance, since we don't need to touch extra metaslabs on each vdev to respect the min distance. Sponsored by: iXsystems, Inc. Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c ============================================================================== --- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c Wed Oct 3 15:34:49 2018 (r339151) +++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c Wed Oct 3 15:35:27 2018 (r339152) @@ -1090,7 +1090,7 @@ metaslab_group_fragmentation(metaslab_group_t *mg) */ static boolean_t metaslab_group_allocatable(metaslab_group_t *mg, metaslab_group_t *rotor, - uint64_t psize, int allocator) + uint64_t psize, int allocator, int d) { spa_t *spa = mg->mg_vd->vdev_spa; metaslab_class_t *mc = mg->mg_class; @@ -1131,6 +1131,13 @@ metaslab_group_allocatable(metaslab_group_t *mg, metas if (mg->mg_no_free_space) return (B_FALSE); + /* + * Relax allocation throttling for ditto blocks. Due to + * random imbalances in allocation it tends to push copies + * to one vdev, that looks a bit better at the moment. + */ + qmax = qmax * (4 + d) / 4; + qdepth = refcount_count(&mg->mg_alloc_queue_depth[allocator]); /* @@ -1151,7 +1158,7 @@ metaslab_group_allocatable(metaslab_group_t *mg, metas */ for (mgp = mg->mg_next; mgp != rotor; mgp = mgp->mg_next) { qmax = mgp->mg_cur_max_alloc_queue_depth[allocator]; - + qmax = qmax * (4 + d) / 4; qdepth = refcount_count( &mgp->mg_alloc_queue_depth[allocator]); @@ -3437,7 +3444,7 @@ top: */ if (allocatable && !GANG_ALLOCATION(flags) && !try_hard) { allocatable = metaslab_group_allocatable(mg, rotor, - psize, allocator); + psize, allocator, d); } if (!allocatable) {
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201810031535.w93FZR7e056647>