https://bugzilla.novell.com/show_bug.cgi?id=638745 https://bugzilla.novell.com/show_bug.cgi?id=638745#c0 Summary: really poor flush performance on unmount Classification: openSUSE Product: openSUSE 11.3 Version: Final Platform: Other OS/Version: Other Status: NEW Severity: Normal Priority: P5 - None Component: Kernel AssignedTo: kernel-maintainers@forge.provo.novell.com ReportedBy: jnelson-suse@jamponi.net QAContact: qa@suse.de Found By: --- Blocker: --- User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.8) Gecko/20100723 SUSE/3.6.8-0.1.1 Firefox/3.6.8 I have a system where, periodically, filesystems undergo a bunch of mounting, copying, and then unmounting. I noticed a change with openSUSE 11.3, and it was not for the better. I believe I've narrowed down a test case: 1. format a new filesystem (xfs, ext4, btrfs, etc...) 2. copy a bunch of stuff (not large files, preferably) to the filesystem (cp, rsync, cpio, whatever) (even a few 10's of MB should be sufficient, but I don't know for sure) 3. *don't issue sync* 4. umount the filesystem 5. watch I/O grind to a halt and the cached buffers take a _very_ long time to get to disk. Expecting to see flush I/O in the neighborhood of 30-60 MB/s, I saw mere hundred's of KB per second. Repeat again, but this time in step 3 issue a sync. I don't recall seeing the horrible flush-on-umount performance with openSUSE 11.2 When I first encountered this, I thought the system was hung. The disk light was steadily lit, but the umount call went on for minutes and minutes. Please note that I haven't had 100% success in replicating this, but more often than not, the test works. I *am* using LVM, but I've seen the behavior where the LVM is on a software raid device and where it is on raw disk and also where it is on a luks-formatted encrypted volume. Reproducible: Always Steps to Reproduce: 1. 2. 3. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.