> You have quite a bit of memory in your 'Old Generation'. You need to determine > what you're allocating that isn't being released.
We have a fairly substantial amount of data that is loaded on startup and remains for the duration. This probably accounts for part of the old-gen usage. I also see that this number increases _and_ decreases over time. My understanding is that this indicates that we have some long-lived objects, but when a full-gc is forced they get cleaned up as well. Am I understanding this correctly? > How many sessions do you have active when the problem occurs? I'm not sure - what is the best way to find this out? > What is your session timeout? The default of 30 minutes. > What are you putting into your sessions (how much is held by each)? Very little - a handful (~5) smallish (100 char) strings. > Are you using any caching technologies like ehCache or hibernate caching? > not allowing caches to expire can eat up memory in the Old Generation space. Nope. > We use a product called LambdaProbe to monitor our tomcat instances. > It's very helpful to count sessions, see what's in them, and to watch > the memory and requests in real-time. I will check this out. Thanks for the suggestion. > If you really *need* everything you're storing and you don't have any > low hanging fruit, you may just need to run with more memory. If you > could test such a configuration you may find that the memory utilization > stabilizes at an acceptable level. This is part of my confusion, turning the Xmx value up seems to have no effect on the problem. A while back I did a bunch of investigation with gclogging and each tomcat instance seemed to level off it's usage at around 120M. So my guess is that we are not dealing with a standard growing of objects over time, but perhaps a case of something going awry that throws us into the OutOfMemory case. But I'm struggling with how to catch that something. --------------------------------------------------------------------- To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
