From ebf8e3a237d4720e3a85fb3a168917ead4ba25d1 Mon Sep 17 00:00:00 2001 From: Brian Behlendorf Date: Thu, 19 Apr 2012 15:55:28 -0700 Subject: [PATCH] Illumos #1909: disk sync write perf regression when slog is used post oi_148 Reviewed by: Matt Ahrens Reviewed by: Eric Schrock Reviewed by: Robert Mustacchi Reviewed by: Bill Pijewski Reviewed by: Richard Elling Reviewed by: Steve Gonczi Reviewed by: Garrett D'Amore Reviewed by: Dan McDonald Reviewed by: Albert Lee Approved by: Eric Schrock Refererces to Illumos issue: https://www.illumos.org/issues/1909 Signed-off-by: Brian Behlendorf Closes #680 --- module/zfs/metaslab.c | 4 ++-- module/zfs/zio.c | 19 ++++++++++++++----- 2 files changed, 16 insertions(+), 7 deletions(-) diff --git a/module/zfs/metaslab.c b/module/zfs/metaslab.c index b089f1e..c33c5e8 100644 --- a/module/zfs/metaslab.c +++ b/module/zfs/metaslab.c @@ -20,7 +20,7 @@ */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. - * Copyright (c) 2011 by Delphix. All rights reserved. + * Copyright (c) 2012 by Delphix. All rights reserved. */ #include @@ -38,7 +38,7 @@ * avoid having to load lots of space_maps in a given txg. There are, * however, some cases where we want to avoid "fast" ganging and instead * we want to do an exhaustive search of all metaslabs on this device. - * Currently we don't allow any gang or dump device related allocations + * Currently we don't allow any gang, zil, or dump device related allocations * to "fast" gang. */ #define CAN_FASTGANG(flags) \ diff --git a/module/zfs/zio.c b/module/zfs/zio.c index 149088d..206ed9a 100644 --- a/module/zfs/zio.c +++ b/module/zfs/zio.c @@ -20,7 +20,7 @@ */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. - * Copyright (c) 2011 by Delphix. All rights reserved. + * Copyright (c) 2012 by Delphix. All rights reserved. * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved. */ @@ -2317,13 +2317,22 @@ zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp, blkptr_t *old_bp, ASSERT(txg > spa_syncing_txg(spa)); - if (use_slog) + /* + * ZIL blocks are always contiguous (i.e. not gang blocks) so we + * set the METASLAB_GANG_AVOID flag so that they don't "fast gang" + * when allocating them. + */ + if (use_slog) { error = metaslab_alloc(spa, spa_log_class(spa), size, - new_bp, 1, txg, old_bp, METASLAB_HINTBP_AVOID); + new_bp, 1, txg, old_bp, + METASLAB_HINTBP_AVOID | METASLAB_GANG_AVOID); + } - if (error) + if (error) { error = metaslab_alloc(spa, spa_normal_class(spa), size, - new_bp, 1, txg, old_bp, METASLAB_HINTBP_AVOID); + new_bp, 1, txg, old_bp, + METASLAB_HINTBP_AVOID | METASLAB_GANG_AVOID); + } if (error == 0) { BP_SET_LSIZE(new_bp, size); -- 1.8.3.1