[PATCH 01/16] xfs: reduce the number of CIL lock round trips during commit

[Alex Elder]

On Wed, 2010-09-22 at 16:44 +1000, Dave Chinner wrote:
> From: Dave Chinner <dchinner at redhat.com>
> 
> When commiting a transaction, we do a lock CIL state lock round trip
> on every single log vector we insert into the CIL. This is resulting
> in the lock being as hot as the inode and dcache locks on 8-way
> create workloads. Rework the insertion loops to bring the number
> of lock round trips to one per transaction for log vectors, and one
> more do the busy extents.
> 
> Also change the allocation of the log vector buffer not to zero it
> as we copy over the entire allocated buffer anyway.
> 
> This patch also includes a structural cleanup to the CIL item
> insertion provided by Christoph Hellwig.
> 
> Signed-off-by: Dave Chinner <dchinner at redhat.com>

Looks good.

Reviewed-by: Alex Elder <aelder at sgi.com>