 | | | "Out of Memory: Killed process " errors on server running Oracle | "Out of Memory: Killed process " errors on server running Oracle 2007-07-25 - By Eric Sisler
Back
Hi Gene,
> We're still weighing the options on our end. We plan on upgrading to
> the update 9 kernel and seeing if that resolves anything. Also we're
> adding another server to the cluster to see if that helps alleviate
> the problem.
Interesting that you're having this problem with RHEL 3. Our older RHEL
3 GSX servers have *never* experienced this type of problem. It's only
as we've been upgrading to RHEL 4 & VMware server that this problem
began to appear. I initially thought the first server I upgraded was
having issues with physical RAM.
A couple of options, which may or may not alleviate your problem. Tried
on RHEL 4 / 2.6.x kernel, so the 2.4.x kernels may be a little
different:
Check status of oom-killer:
# more /proc/sys/vm/oom-kill
Turn oom-killer off/on:
echo "0" > /proc/sys/vm/oom-kill
echo "1" > /proc/sys/vm/oom-kill
To make this change take effect at boot time, add the following
to /etc/sysctl.conf:
vm.oom-kill = 0
For processes that would have been killed, but weren't because the oom-
killer is disabled, you'll see the following message
in /var/log/messages:
"Would have oom-killed but /proc/sys/vm/oom-kill is disabled"
This seems to be a bit of a two-edged sword with VMware. Processes that
would normally trigger the oom-killer don't get killed. Sometimes
things return to normal after the VM starts up and everything's ok.
Other times the server goes into a downward spiral of heavy RAM
utilization and high CPU load and the only "fix" is a hard reboot.
I'm not entirely sure what triggers the oom-killer. I've noticed it
seems to be a combination of free RAM getting low and a load of 20.00 or
higher. If free RAM gets low but load stays under ~15.00, generally I
have no problems. Is Oracle kicking off a process that causes a similar
situation on your end?
I *thought* I had "solved" the problem by redistributing my virtual
machines to different servers. I started a VM configured with 1.5Gb RAM
on a lightly-loaded, dual quad-core / 16Gb RAM server and the VM got
oom-killed. At this point our old servers running RHEL 3 & VMware GSX
perform better than our new servers running RHEL 4 & VMware Server. Go
figure.
Unless a better solution appears, I'm considering rolling back to RHEL 3
(keeping VMware Server) on our servers.
Hope you have better luck on your end.
-Eric
--
Eric Sisler <esisler@(protected)>
Library Network Specialist
Westminster Public Library
Westminster, CO USA
Linux - Don't fear the Penguin.
Want to know what we use Linux for?
Visit http://wallace.westminster.lib.co.us/linux
--
Taroon-list mailing list
Taroon-list@(protected)
https://www.redhat.com/mailman/listinfo/taroon-list
|
|
|