I'm monitoring some CentOS 5 servers running Sun Java. We have set things up so 2048 MB of RAM are available for the base operating system, taking into account the xMx and permgen settings. What we're seeing is the swap space getting used up, and not released. Is this normal behavior? Performance doesn't seem to be affected, however I'm a bit concerned that the swap file is completely full:
free -m total used free shared buffers cached Mem: 9993 9945 48 0 174 1695 -/+ buffers/cache: 8074 1919 Swap: 2047 2033 14
Here are the xMx and permgen settings: -Xms7177m -Xmx7177m -XX:MaxPermSize=768m
Apart from Java/Tomcat/Apache and some HP hardware monitoring tools we are not running anything else on this server.