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| author | Matthew Ahrens <mahrens@delphix.com> | 2017-03-24 14:34:50 -0700 |
|---|---|---|
| committer | Prakash Surya <prakash.surya@delphix.com> | 2017-06-05 22:13:57 -0700 |
| commit | 5b062782532a1d5961c4a4b655906e1238c7c908 (patch) | |
| tree | 54233f77820104b25de9486f0c3cffea8fa09c16 /usr/src/uts/common/fs/zfs/vdev_queue.c | |
| parent | adaec86ad212d9fd756bee322934fa54d1258605 (diff) | |
| download | illumos-gate-5b062782532a1d5961c4a4b655906e1238c7c908.tar.gz | |
8005 poor performance of 1MB writes on certain RAID-Z configurations
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Diffstat (limited to 'usr/src/uts/common/fs/zfs/vdev_queue.c')
| -rw-r--r-- | usr/src/uts/common/fs/zfs/vdev_queue.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/usr/src/uts/common/fs/zfs/vdev_queue.c b/usr/src/uts/common/fs/zfs/vdev_queue.c index b4a84914d5..3d2014579c 100644 --- a/usr/src/uts/common/fs/zfs/vdev_queue.c +++ b/usr/src/uts/common/fs/zfs/vdev_queue.c @@ -24,7 +24,7 @@ */ /* - * Copyright (c) 2012, 2014 by Delphix. All rights reserved. + * Copyright (c) 2012, 2017 by Delphix. All rights reserved. * Copyright (c) 2014 Integros [integros.com] */ @@ -539,7 +539,7 @@ vdev_queue_aggregate(vdev_queue_t *vq, zio_t *zio) /* * Walk backwards through sufficiently contiguous I/Os - * recording the last non-option I/O. + * recording the last non-optional I/O. */ while ((dio = AVL_PREV(t, first)) != NULL && (dio->io_flags & ZIO_FLAG_AGG_INHERIT) == flags && @@ -560,10 +560,14 @@ vdev_queue_aggregate(vdev_queue_t *vq, zio_t *zio) /* * Walk forward through sufficiently contiguous I/Os. + * The aggregation limit does not apply to optional i/os, so that + * we can issue contiguous writes even if they are larger than the + * aggregation limit. */ while ((dio = AVL_NEXT(t, last)) != NULL && (dio->io_flags & ZIO_FLAG_AGG_INHERIT) == flags && - IO_SPAN(first, dio) <= zfs_vdev_aggregation_limit && + (IO_SPAN(first, dio) <= zfs_vdev_aggregation_limit || + (dio->io_flags & ZIO_FLAG_OPTIONAL)) && IO_GAP(last, dio) <= maxgap) { last = dio; if (!(last->io_flags & ZIO_FLAG_OPTIONAL)) @@ -594,10 +598,16 @@ vdev_queue_aggregate(vdev_queue_t *vq, zio_t *zio) } if (stretch) { - /* This may be a no-op. */ + /* + * We are going to include an optional io in our aggregated + * span, thus closing the write gap. Only mandatory i/os can + * start aggregated spans, so make sure that the next i/o + * after our span is mandatory. + */ dio = AVL_NEXT(t, last); dio->io_flags &= ~ZIO_FLAG_OPTIONAL; } else { + /* do not include the optional i/o */ while (last != mandatory && last != first) { ASSERT(last->io_flags & ZIO_FLAG_OPTIONAL); last = AVL_PREV(t, last); @@ -609,7 +619,7 @@ vdev_queue_aggregate(vdev_queue_t *vq, zio_t *zio) return (NULL); size = IO_SPAN(first, last); - ASSERT3U(size, <=, zfs_vdev_aggregation_limit); + ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); aio = zio_vdev_delegated_io(first->io_vd, first->io_offset, abd_alloc_for_io(size, B_TRUE), size, first->io_type, |