Huge resident size despite small heap

[Stefan Reich]

Quick follow-up: The only GC-related command line options I use are

  -XX:MaxHeapFreeRatio=20 -XX:MinHeapFreeRatio=10
-XX:+UseStringDeduplication

On Sun, 27 Mar 2022 at 23:14, Stefan Reich <
stefan.reich.maker.of.eye at googlemail.com> wrote:

> Hi, I am currently running OpenJDK 16 on my server (will upgrade to 17
> when I'm sure none of my code is dependent on illegal accesses). OS is
> Ubuntu 18.
>
> I am noticing that a long running server process eventually (after a few
> days) grows enormously in its resident size. Right now it is at 7 GB.
> Performing a GC doesn't get it any lower.
>
> The weird part is that the process is run with -Xmx2g, and currently used
> heap according to java.lang.Runtime is only 400 MB after GC, going up to at
> most 1 GB in operation.
>
> How do these numbers fit together?
>
> I've seen the resident size even higher (13+ GB), and at that point I
> noticed the process getting significantly slower too (web pages taking 1-2
> seconds to load instead of near instant).
>
> At a typical moment in time, no Java threads are running (I monitor this
> every second).
>
> An obvious suspect is of course any native library loaded. The only native
> library in use is, I think, the OSHI library.
>
> Any ideas why this might be happening?
>
> Many greetings,
> Stefan
>
> --
> == Gaz.AI ==
>


-- 
== Gaz.AI ==
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