NFS: Fix writeback performance issue on cache invalidation
authorTrond Myklebust <Trond.Myklebust@netapp.com>
Mon, 5 Aug 2013 17:26:31 +0000 (13:26 -0400)
committerTrond Myklebust <Trond.Myklebust@netapp.com>
Wed, 7 Aug 2013 21:07:40 +0000 (17:07 -0400)
commitf8806c843f88a6b7d657cf24c3682bc2efda6fdb
tree6ac028b704a1f3c78f7dc98cc5fbf1de5e3a543c
parent786615bc1ce84150ded80daea6bd9f6297f48e73
NFS: Fix writeback performance issue on cache invalidation

If a cache invalidation is triggered, and we happen to have a lot of
writebacks cached at the time, then the call to invalidate_inode_pages2()
will end up calling ->launder_page() on each and every dirty page in order
to sync its contents to disk, thus defeating write coalescing.
The following patch ensures that we try to sync the inode to disk before
calling invalidate_inode_pages2() so that we do the writeback as efficiently
as possible.

Reported-by: William Dauchy <william@gandi.net>
Reported-by: Pascal Bouchareine <pascal@gandi.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: William Dauchy <william@gandi.net>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
fs/nfs/inode.c