Andy Seaborne wrote:
> Very roughly, Java takes about 0.5G over the heap size so 2.4GB is what to 
> expect before the runtime triggers a full GC and the full GC will reduce the 
> heap in uses. The process size will not shrink.

We have experienced some sort of degenerate behavior with fuseki where the 
JVM’s non-heap memory gets much larger than normal.  (Andy, you may recall that 
I sent you heap dumps and other debug information a couple years back.)

We have never figured out the solution, and periodically restart the service to 
compensate.  We are running what is at this point a quite old version of 
fuseki, so some related bug may have been found & fixed.  However, I do try to 
watch the release notes and didn’t notice anything obviously related.

in general, Andy’s right about the memory usage of Java above & beyond the heap 
- but there can be significant exceptions. For example, we use Solr, which uses 
java’s NIO facility.  NIO uses out-of-heap memory, and we regularly see 4GB 
additional usage.

Thanks
danno

Reply via email to