Java Linux Memory Usage

[thomasolsen]

Hi,

I have a java program running on Linux Debian using jre 1.6 (I have tried under 1.5 with excatly the same results). As the program is running as a service I have been watching the memory usage from within linux, as well as using JProfiler. When looking at it from the operating system using ps or top I can see that the is a small increase in memory consumption every hour and never decreases again (like a memory leak).

So I looked at JProfiler and when looking at the memory heap it stays constant (as I started the program with -Xms32M and -Xmx32M). Also from within Jprofiler I checked the non heap memory and after setting a lower maximum on the code cache it look not to allocate memory more memory here.

So now with the Heap and non heap memory constant I wouldn't expect the process memory in linux to grow, but it does.

The profile of the java programs memory uasge from JProfiler show that everything is ok in regards to garbage collection

Can I trust the output from ps and top or is there a better way to determine the memory usage from the operating system?

Is this a problem or am I looking at something complete normal?

Thanks for you help

Thomas

[JosAH]

Let the thing run (and keep it busy) for a couple of days. It's a nasty thing, that
can't be easily nailed down. I had similar behaviour once and only after a couple
of days I could spot the memory leak. OTOH, sometimes the amount of memory
allocated to the process grows and falls back again after some time. Best of
luck with that nasty behaviour. Let it run for a couple of days.

kind regards,

Jos

[javaandy]

the 'top', 'ps', 'free' command of the linux os seems not to be useful for checking the memory info. your application may not get a memory leak, and the increase of the Memory Usage is just because you occupy more cache, and linux would release it some day, just wait for more time.

hope it works,
good luck

andy