diff options
authorDave Chinner <dchinner@redhat.com>2010-09-08 09:00:22 +0000
committerAlex Elder <aelder@sgi.com>2010-09-10 10:16:54 -0500
commit51749e47e191db8e588ad5cebea731caf7b705d7 (patch)
parenta122eb2fdfd78b58c6dd992d6f4b1aaef667eef9 (diff)
xfs: log IO completion workqueue is a high priority queue
The workqueue implementation in 2.6.36-rcX has changed, resulting in the workqueues no longer having dedicated threads for work processing. This has caused severe livelocks under heavy parallel create workloads because the log IO completions have been getting held up behind metadata IO completions. Hence log commits would stall, memory allocation would stall because pages could not be cleaned, and lock contention on the AIL during inode IO completion processing was being seen to slow everything down even further. By making the log Io completion workqueue a high priority workqueue, they are queued ahead of all data/metadata IO completions and processed before the data/metadata completions. Hence the log never gets stalled, and operations needed to clean memory can continue as quickly as possible. This avoids the livelock conditions and allos the system to keep running under heavy load as per normal. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index d72cf2bb054a..286e36e21dae 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -1932,7 +1932,8 @@ xfs_buf_init(void)
if (!xfs_buf_zone)
goto out;
- xfslogd_workqueue = create_workqueue("xfslogd");
+ xfslogd_workqueue = alloc_workqueue("xfslogd",
if (!xfslogd_workqueue)
goto out_free_buf_zone;

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