On 01/09/2012 06:08 PM, Sergiu Dumitriu wrote:
On 01/09/2012 11:01 AM, Kaya Saman wrote:
Hi,
just checked through my logs and found this:
SEVERE: The web application [/xwiki] created a ThreadLocal with key of
type [org.apache.log4j.helpers.ThreadLocalMap] (value
[org.apache.log4j.helpers.ThreadLocalMap@2ff7ac92]) and a value of type
[java.util.Hashtable] (value
[{url=http://wiki.optiplex-networks.com/xwiki/bin/export/XWiki/ResetPasswordRequestClass?format=xar&name=XWiki.ResetPasswordRequestClass&pages=XWiki.ResetPasswordRequestClass}])
but failed to remove it when the web application was stopped. This is
very likely to create a memory leak.
it's probably the reason my Java instance is so unstable and hogging my
systems swap. Can anything be done to sort it?
That's not severe, it's only triggered when undeploying XWiki. When
shutting down Tomcat, it doesn't mean anything since the JVM is going
to exit anyway. The only real concern is when you redeploy the war at
runtime, through the container's management interface, and Tomcat does
handle that, it just reports it as a warning.
Well for a while I've been trying to debug 'extreme' memory usage by
Tomcat/Java and it seems it's a viable culprit.
Not so much for my wiki site but my www which actually should have
smaller footprint then my wiki since it has much less information in it
or attachments. The only thing that may use more memory could be the
flash video on the main page.
Out of 4GB memory this is what's happened to my system:
Mem: 1738M Active, 266M Inact, 1673M Wired, 25M Cache, 408M Buf, 125M Free
Swap: 2327M Total, 2276M Used, 51M Free, 97% Inuse
PID USERNAME THR PRI NICE SIZE RES STATE C TIME WCPU COMMAND
51547 www 46 44 0 3557M 993M ucond 1 9:46 0.00% java
which is 64bit too.....
The RES part of top has gone down but used to be round 1.6GB??
If it's not a memory leak as such then are there any performance tips
that I can use that will directly lower the memory usage?
I have checked out the 'performance tuning' page on the site, hence I
was directly working in it for the robots.txt stuff :-)
Regards,
Kaya