What is normal for memory usage in Jira Service Desk?

Jason Freeman

We have just installed Jira Service Desk on CentOS, and we are not using it in production yet.

The virtual machine that runs JSD has 8 gigabytes of RAM and has no other services running; the VM is dedicated to JSD.

In the System Info area, I see the following regarding memory usage:

Java VM Memory Statistics

Total Memory 747 MB

Free Memory 34 MB

Used Memory 713 MB

Memory Graph 4% Free

Having only 4% free doesn't seem good, but I don't know what's normal. And only using 747 MB seems low when the VM has 8 gigabytes of RAM, too, but again -- I don't know what is considered normal.

We are using JSD 3.11.

Andy Heinzer

Most Jira installs default the jvm memory max (Xmx) parameter to 768m.   Out of the box, this is fine for most evaluation and small installations.   However as you add users, additional plugins to Jira, custom fields, and more issues, you might find you need to increase the memory Jira can use.    However I would also caution you against increasing this value too high.   

If the heap is too small, Jira will tend to have lots of pauses to perform Java garbage collection.   But the downsize of having too large a heap can be worse in some cases because while you might not have as many garbage collection events, when they do happen in these larger heaps, the pauses to the application become more noticeable and in longer duration until complete.

I recommend checking out the Jira Sizing Guide.  It can help provide an expectation of what kind of system resources you are going to need for Jira now and possibly in the future if you are expecting your instance to grow.

Given the system has 8GB of memory, I would set your Xmx parameter to somewhere between 1g and 2g (or 1024m and 2048m).   You need to leave a good deal of memory available to the operating system, database, and other services.