From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q2FIEJ8p168814 for ; Thu, 15 Mar 2012 13:14:20 -0500 Date: Thu, 15 Mar 2012 13:14:26 -0500 From: Ben Myers Subject: Re: [PATCH 10/10] xfs: don't cache inodes read through bulkstat Message-ID: <20120315181426.GO7762@sgi.com> References: <1331095828-28742-1-git-send-email-david@fromorbit.com> <1331095828-28742-11-git-send-email-david@fromorbit.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1331095828-28742-11-git-send-email-david@fromorbit.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com On Wed, Mar 07, 2012 at 03:50:28PM +1100, Dave Chinner wrote: > From: Dave Chinner > > When we read inodes via bulkstat, we generally only read them once > and then throw them away - they never get used again. If we retain > them in cache, then it simply causes the working set of inodes and > other cached items to be reclaimed just so the inode cache can grow. > > Avoid this problem by marking inodes read by bulkstat as not to be > cached and check this flag in .drop_inode to determine whether the > inode should be added to the VFS LRU or not. If the inode lookup > hits an already cached inode, then don't set the flag. If the inode > lookup hits an inode marked with no cache flag, remove the flag and > allow it to be cached once the current reference goes away. > > Inodes marked as not cached will get cleaned up by the background > inode reclaim or via memory pressure, so they will still generate > some short term cache pressure. They will, however, be reclaimed > much sooner and in preference to cache hot inodes. > > Signed-off-by: Dave Chinner > --- > fs/xfs/xfs_iget.c | 8 ++++++-- > fs/xfs/xfs_inode.h | 4 +++- > fs/xfs/xfs_itable.c | 3 ++- > fs/xfs/xfs_super.c | 17 +++++++++++++++++ > 4 files changed, 28 insertions(+), 4 deletions(-) > > diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c > index 93fc1dc..20ddb1e 100644 > --- a/fs/xfs/xfs_iget.c > +++ b/fs/xfs/xfs_iget.c > @@ -290,7 +290,7 @@ xfs_iget_cache_hit( > if (lock_flags != 0) > xfs_ilock(ip, lock_flags); > > - xfs_iflags_clear(ip, XFS_ISTALE); > + xfs_iflags_clear(ip, XFS_ISTALE | XFS_IDONTCACHE); If XFS_IGET_DONTCACHE is set, maybe you don't want to clear XFS_IDONTCACHE. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs