CentOS - Mar 2010 - CentOS server running java - won't let go of swap

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.
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.centos.org/pipermail/centos/attachments/20100307/7be51ff1/attachment-0002.html>

Sean Carolan wrote:
> 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.
> 
I think Xms/x is java's heap space for program object storage.  It
doesn't take
into account the space needed for the JVM itself.  Top should show you the 
actual memory usage - along with any other programs that might be using a lot.

-- 
   Les Mikesell
    lesmikesell at gmail.com

> I'm monitoring some CentOS 5 servers running Sun Java. ?We have set
things
Out of curiosity, which version of Sun Java do you use precisely?

I had memory issues with the the Java OpenJDK 1.6 (b09) provided by
stock CentOS and upgraded to Java OpenJDK 1.6 b16.