Bart: What is the topology of your test system?
At Clemson, when running tests on a SUN box with 8 Quad-Core AMD Opteron Processor 2356 and the latest cvs version of pvfs, I was getting a lot of timing issues when running 4 servers on the one box, justing using the cp command. I am still trying to run down the problems. Becky -- Becky Ligon PVFS Developer Clemson University 864-650-4065 > I can reproduce it fairly reliably with my test case; I average somewhere > around a 50% chance of generating one or more of these files per test. My > preliminary testing with db 4.8.30 is encouraging. I will update this > thread > with any conclusions. > > Bart. > > > > On Tue, Oct 19, 2010 at 3:41 PM, Phil Carns <[email protected]> wrote: > >> >> Removing the metadata object for a file does indeed produce the same >>> symptoms we are seeing. It produces a similar effect on 2.8 as well. I >>> believe I was working with Sam and possibly you on this a few weeks ago >>> but >>> had to drop it for something more urgent. Our conversation can be found >>> here: >>> >>> >>> http://www.beowulf-underground.org/pipermail/pvfs2-developers/2010-June/004605.html >>> >>> In 2.8, pvfs2-rm does not currently remove the file entries. Sam had >>> the >>> same ENOTENT fix for 2.8. After creating a file and removing the >>> metadata >>> object, it allows the file entry to be removed. >>> >> >> Ah! Believe it or not I had forgotten about that thread, but Sam's fix >> must have stuck in my head subconsciously because I figured out where to >> add >> that check in 2.6 pretty quickly :) >> >> We need to get this fix into cvs if it isn't there already... >> >> >> I believe Jim Kusznir may have been experiencing similar issues when he >>> posted to the Users list here: >>> >>> >>> http://www.beowulf-underground.org/pipermail/pvfs2-users/2010-September/003186.html >>> >>> It appears that something is still triggering this issue in 2.8. Based >>> on >>> my own anecdotal evidence with 2.6 and 2.8, it looks like it can happen >>> when >>> a file system is getting hammered with creates and/or deletes. My test >>> case >>> to reproduce on 2.8 involved several threads executing a script that >>> creates, opens, writes, and then deletes a file many thousands of >>> times. The >>> problems we have had on 2.6 also correlate to heavy loads of file >>> creations >>> and deletions. >>> >>> Anyone have thoughts on why some files are getting left without their >>> metadata object? >>> >>> Bart. >>> >> >> I think Becky had some good ideas. How hard is this to reproduce? Can >> you >> do it pretty reliably with your test case? >> >> -Phil >> > _______________________________________________ > Pvfs2-developers mailing list > [email protected] > http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers > _______________________________________________ Pvfs2-developers mailing list [email protected] http://www.beowulf-underground.org/mailman/listinfo/pvfs2-developers
