[Hawkular-dev] Memory-usage of Hawkular-services

[Heiko W.Rupp]

On 11 Oct 2016, at 8:42, Heiko W.Rupp wrote:

> Hey,
>
> tl;dr: we need to investigate heap usage - especially in the case of 
> compression
> kicking in - it looks like there could be a memory leak. Compression 
> timing seems
> mostly ok.

Looks like we are making some progress

- metric forwarding to alerts seems to do some memory-wise
heavy work, that can be reduced (hwkmetrics-507 and -508 and 
hawkular-1130 iirc)
- internal hsqldb uses a lot of memory
   - that is "only" a developer concern
- using postgres does not exhibit the memory usage for caching as does 
hsqldb, but
   - the postgres driver in inventory (v...1201) seems to use finalizers 
too much
      - we are investigating to use a newer driver that may perform 
better

I just replaced in a local copy inventory 0.20 with 0.19.3 and this 
seems to be
smoother sailing - a lot less finalizers that also hold less memory.

I did try to run with -XX:+UseStringDeduplication which requires 
-XX:+UseG1GC, but
according to MAT it did not have an effect for me. We may want to look 
into
string interning for the future like we did in JON.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/hawkular-dev/attachments/20161014/e4788ee3/attachment.html