Hi Marcy, Sorry to bother you about this, but did you ever get a resolution? We've seen this as well and haven't yet gotten much relief from Novell, so I started poking around myself and tracked it down to (in the kernel package changelog):
* Thu May 23 2013 [email protected] - Refresh patches.fixes/mm-vmscan-Block-kswapd-if-it-is-encountering-pages-under-writeback-fix-2.patch - commit ee1efa5 I just kept removing patches until I got a kernel that didn't exhibit the problem. Removing that patch it works fine...put the patch back on and the problem comes back. The problem is that the patch is on in upstream as well, but upstream kernels do not have the problem either. I suspect it's because of this commit: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/mm/vmstat.c?id=6e543d5780e36ff5ee56c44d7e2e30db3457a7ed I'm going to try building a vanilla kernel without that and see if the problem returns. Unfortunately, that specific patch looks to be a bugger to backport to our SP3 kernel. :-( Thanks, Leland On 11/1/2013 12:30 PM, Marcy Cortes wrote:
We're experiencing a problem with kernel 3.0.93 (SP3). It seems on servers that are memory constrained can go into a loop doing tons of i/o - 8000+ / second. It seems to happen with things like WAS deploys. We may have also been able to recreate use a simple perl array. Has anyone else seen this? Yes, we have a high priority SR opened with SUSE. Oddly we have seen something like this after a kernel update on SP2. That was solved by changing vm.swappiness to something > 0. We have put it back to 60 (the default) and still get the problem. Upping the memory solves it, but obviously, that's not something we want to be doing, especially in our constrained dev environment. Marcy ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
