Re: [xwiki-users] Xwiki memory leak?

Notice that PermGen space is not java heap. Therefore I suppose it is unlikely to have anything to do with attachment. Not in this case. You may want to check if other web applications are deployed to your tomcat instance - and if they use many classes/libs. Then you may want to increase the "-XX:MaxPermSize" or undeploy some webapps.

Pavel On Thu, May 29, 2008 at 9:16 PM, Richard V. &lt;xgcom(a)hotmail.com&gt; wrote: > Thanks for the prompt response. > > The answer regarding to large attachments is no. I don't have any large > attachments in any of my pages. > > The "out-of-memory" error happens without any page in common, but when that > happens, any other page that I want to access will result with the same > error. It is like once memory has run out, it is unrecoverable. > > You may be right regarding to the DB connections threads not receiving the > shutdown message, but that does not explain why i can't properly shutdown > tomcat with XWiki deployed. Again, Tomcat shutdows smoothly when XWiki is > not present. I don't mind not being able to gracefully shutdown tomcat, > since i can always do "kill -9 <pid>", but what annoys me is the > out-of-memory error after certain time. > > What could be the problem? This is happening on my development machine, but > I am going to build another Linux machine right now and try if I can > replicate the problem. > > Richard > >> Date: Thu, 29 May 2008 19:46:20 +0200 >> From: sergiu(a)xwiki.com >> To: users(a)xwiki.org >> Subject: Re: [xwiki-users] Xwiki memory leak? >> >> Richard V. wrote: >>> Hi XWiki users, >>> >>> I have encountered a problem where after running XWiki on my tomcat > server for a week, i get an java.lang.OutOfMemoryError: PermGen space error. > It appears that xwiki consumed all the java heap space. I believe the > problem may be related to unreleased DB connections because, I noticed that > everytime I try to shutdown tomcat, it hangs with xwiki deployed, also by > running "ps aux" i see the postgresql connection processes belonging to > xwiki still running. I tried deploying another application that uses > hibernate + postgresql on the same tomcat running xwiki, and upon shutting > down the server, all db connection processes from the other application > gracefully terminate but not the ones from xwiki. >>> My question is does anyone ever had this problem before? If so what is > the solution? >>> Solutions that I have tried but did NOT work: >>> 1- Increase java heap with -Xmx512m >>> 2- Reduce the maximum and minimum idle DB connections >>> >>> My system specs: >>> >>> OS: Linux ubuntu kernel 2.6.20 >>> Java: 1.6.0_05-13 >>> Xwiki: 1.4 (binary distribution) >>> Posgresql: 8.2.6 >>> Total RAM: 1Gb >>> >> AFAIK, there isn't a leak, but a somewhat "normal" behavior caused by >> the cache settings. The cache is configured to be a fixed size LRU >> cache, so if you store large entries in the cache, they will be kept >> there. The OOM error appears mostly when there are large attachments in >> the database. You should either reduce the size of the attachment cache >> or increase the memory. >> >> The shutdown problem is a different thing, it doesn't have anything to >> do with the database connections. I think it is because of some threads >> we're spawning that don't receive the shutdown message (the quartz >> scheduler for example). A memory leak regarding DB connections would >> mean there are thousands of open connections to the database, but I am >> pretty sure that's not the case, right? >> >> So, the main question is: Are there many & pretty large attachments in >> the wiki?