Give jenkins more memory

[magik6k]

By default Jenkins uses 256M, which makes it painfully slow (caused by GC) for any deployment that has more than few light jobs. Picked 4G as it seems to be a reasonable amount of memory.

(I'm not sure if this is the right place to put this)

[victorb]

Thanks for the patch @magik6k. You know any way of checking if this is already set? Because if I run docker stats jenkins, I can see that the container is using 2.1GB of memory already. Just want to be able to verify that it's actually using more memory. The box also has 16GB of memory, so we can increase it to 12GB or something like that, nothing but jenkins runs there basically.

[magik6k]

As far as I know it is set via java argument, so do ps aux | grep java | grep jenkins and then look for -Xmx[something]m

Java has large overhead, Xmx is only the heap memory - it's not recommended to assign more than 50% of host memory.

You can debug memory/cpu use with tools like https://visualvm.github.io/, AFAIK possible to use it remotely.