On Thu, 2002-08-22 at 16:43, Greg Freemyer wrote: > All, > > I have not been successful at getting reliable Read-Only snapshots of XFS via LVM. Since XFS is being used in Enterprise quality applications, I suggest this is a major shortcoming that should be prioritized. > > BTW: Are there any snapshot related tests in the XFS regression tests? No, there aren't. Frankly, snapshot has not gotten a lot of attention lately. > When a failure occurs the lvcreate --snapshot command will freeze up. If that's the failure, looking at a kdb backtrace of the "stuck" process would be helpful, and might give us an idea of where to look. Testing a CVS kernel for the same behavior would also be a good datapoint. > A manually entered xfs_freeze -u will release the lvcreate. (The VFS-lock patch effectively is calling xfs_freeze -f internally prior to starting the snapshot process.) > FYI: Adrian Head believes that the VFS-lock patch is more reliable than not having it and wrapping the lvcreate --snapshot call with explicit xfs_freeze calls. I have not tried that. If things are working as intended, that should not be the case - the end result should be that xfs runs the same code, whether you did it via a manual userspace command, or the automatic vfs-lock patch. Sending some debug output from kdb would help - but also, take a look at that list of work Steve posted today, and realize that there are lots of things going on at the moment. :) Thanks, -Eric -- Eric Sandeen XFS for Linux http://oss.sgi.com/projects/xfs sandeen@sgi.com SGI, Inc. 651-683-3102 _______________________________________________ linux-lvm mailing list linux-lvm@sistina.com http://lists.sistina.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html
