[colug-432] ulimit

Jon Miller jonebird at gmail.com
Fri Dec 2 14:41:19 EST 2011

You wouldn't want to re-compile your kernel for ulimit value changes.
The root user can adjust your ulimit values and a common way to do
that is via the pam_limits module with it's associated configuration
file at /etc/security/limits.conf. If you're unsure that you've set
your ulimits properly, try inserting a "ulimit -a > /tmp/mylimits.out"
into the RC script.

-- Jon Miller

On Fri, Dec 2, 2011 at 1:50 PM, Mark Aufdencamp <mark at aufdencamp.com> wrote:
> If your 1024 limit is threads, that's the default compiled into the RH
> kernel.  You'll need to custom compile the kernel with a higher value to
> increase that number.  I've had to do that for some heavy traffic Apache
> sites.  If thats truely the area your having problems, you might also
> want to investigate the JVM to native thread mapping .  The JVM doesn't
> necessarily map one-to-one.  This would especially be true if your using
> the IBM JVM rather than Sun's(oops Oracles) JVM.  I remember reading on
> this sometime ago, but its been a while.
> Hope that helps some.
> Mark Aufdencamp
>> -------- Original Message --------
>> Subject: [colug-432] ulimit
>> From: Rick Hornsby <richardjhornsby at gmail.com>
>> Date: Fri, December 02, 2011 11:52 am
>> To: Central OH Linux User Group - 432xx <colug-432 at colug.net>
>> We're running into some issues hitting FD limits, mostly running Websphere on RH5.5.
>> We've been able to raise the limit by adding entries to /etc/security/limits.conf for the user running Websphere, but still don't fully understand how the kernel counts how many FDs a user has open (websphere is the only thing running java but lsof -c /java/ | wc -l sometimes shows a value over the limit w/ no obv issues), if that is the right place to set it, and where the default of 1024 comes from?
>> Further confusing it for me at least is that ulimit is a bash builtin command, but the limits are enforced by the kernel?
>> Any insight would be helpful.
>> thanks!
>> -rj
>> Sent from my iPhone
>> _______________________________________________
>> colug-432 mailing list
>> colug-432 at colug.net
>> http://lists.colug.net/mailman/listinfo/colug-432
> _______________________________________________
> colug-432 mailing list
> colug-432 at colug.net
> http://lists.colug.net/mailman/listinfo/colug-432

More information about the colug-432 mailing list