2009/12/17 Lars Fischer <lfisc...@fast-mail.org> > I have some trouble with a Tomcat running on a vServer Ubuntu 8.04: > > I used an old vServer with 768MB RAM. On this machine I had a Tomcat > running using -XX:MaxPermSize=128m -Xmx256m settings. Tomcat consumed > the given memory and was working fine. >
Was that a 32-bit or 64-bit machine, and a 32-bit or 64-bit Java VM? > Now I switched to a new vServer machine with 1024MB RAM. Is that a 32-bit or 64-bit machine, and a 32-bit or 64-bit Java VM? > I installed the > latest JDK6, downloaded latest Tomcat6 and started it. As result the > htop- > command shows me a virtual memory consumption of 512MB. Together with > additional MySql and httpd the new machine needs much more memory than > on the old machine and sometimes my webapps fail with something like > "java.io.IOException: Cannot run program "env": java.io.IOException: > error=12, Cannot allocate memory" > > This is annoying: the new machine with more RAM gets not enough > memory... > > Where is my mistake? Is it a problem of the vServer? > > I'm guessing slightly, but 64-bit VMs take somewhat more memory as all pointers (and hence all Java references) are 8-byte rather than 4-byte quantities. If you've moved from 32-bit to 64-bit, your memory use will definitely increase. Also... what else has changed? New Tomcat version (what was the old one?), new Java version? (what are the old and new versions?), new MySQL version, new OS version? - Peter
