JIRA VM is using more 12GB memory when JIRA XmX is configure for

[Ashok Singh]

Current JIRA java process Memory is set to Xms3584m -Xmx4068m

when doing top on the box 

%Cpu(s): 0.2 us, 0.4 sy, 0.0 ni, 99.4 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem : 15232996 total, 550176 free, 5315164 used, 9367656 buff/cache
KiB Swap: 0 total, 0 free, 0 used. 9386832 avail Mem

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
18527 jira 20 0 10.4g 3.8g 26064 S 0.0 26.0 131:40.05 java

$ free -m
total used free shared buff/cache available
Mem: 14875 5188 539 88 9148 9168
Swap: 0 0 0

Why is JIRA java process has such a big virtual address space ? do I need to increase RAM on server .

[Rakesh Jogi]

The large virtual memory size reported for the Jira Java process cannot be the only cause for concern. The VIRT value is the actual total virtual address space reserved by the JVM. As a result of this, the virtual memory seems to be larger than the configured heap size value.

From the values you shared, the resident memory should be considered as an important one which is around 3.8 GB. This number matches with the configured Java heap size. This also conveys that the JVM is not actively consuming the full 10.4 GB of physical memory. Apart from this there is still 9 GB left out memory which shows there is no memory pressure now.

So it's not the right way to get to the conclusion that Jira requires additional RAM. Whenever you think you should do memory upgrade, better you have to check and monitor the actual heap utilization and you can decide to proceed. If you increase the heap when it is not required, this will also impact on your performance. Before considering a memory upgrade, it would be advisable to monitor actual heap utilization, garbage collection activity, native memory usage, and overall system memory pressure. Unless you are experiencing OutOfMemoryErrors, excessive garbage collection pauses, etc., increasing server RAM is unlikely to provide any immediate benefit.

If you wish to understand this better and get proper usage steps on how to set the heap size to your application you can refer to this blog, Sizing Your Heap Correctly: Understanding -Xms and -Xmx.

[Gonchik Tsymzhitov]

Hi! 

Because java use not only heap memory, + stack size, code cache, meta space, other things.