From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: ceph on btrfs [was Re: ceph on non-btrfs file systems] Date: Tue, 25 Oct 2011 06:23:30 -0400 Message-ID: <20111025102330.GA18415@infradead.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Christian Brunner , ceph-devel@vger.kernel.org, linux-btrfs@vger.kernel.org To: Sage Weil Return-path: In-Reply-To: List-ID: On Mon, Oct 24, 2011 at 10:06:49AM -0700, Sage Weil wrote: > > - When I run ceph with btrfs snaps disabled, the situation is getting > > slightly better. I can run an OSD for about 3 days without problems, > > but then again the load increases. This time, I can see that the > > ceph-osd (blkdev_issue_flush) and btrfs-endio-wri are doing more work > > than usual. > > FYI in this scenario you're exposed to the same journal replay issues that > ext4 and XFS are. The btrfs workload that ceph is generating will also > not be all that special, though, so this problem shouldn't be unique to > ceph. What journal replay issues would ext4 and XFS be exposed to?