Shoud I use 60GB heap size?

Question

I am wondering setting heap size to more than 32GB will increase performance or not? I have a server with 128GB memory.

As I read, if I increase it to 48GB, the performance will decrease, but what about setting it to 60GB?

Answer 1

No, you shouldn't, increasing your heap size for values higher than 30GB won't increase performance, it will probably make things worse.

Elastic recommends to use a maximum value between 26 GB and 30 GB, depending on your system.

If you are having performance issues you first have to identify if those issues are related to your heap size or not, it could be a disk i/o issue.

You could also spin up another instance on the same machine to increase your cluster.

Answer 2

Basically heap memory depends on your application. What kind of process doing in the application.For the normal applications we starts allocating memory from the 30 % of the total memory.if we have exceptions like Out of Heap Memory then increase it according to requirement.Maximum Heap size we can allocate to application only to 60% of the total memory.This is the best practice that normally followed.