Re: Negative off heap memory?

[Lars Winderling]

Hi Mark,




Best,
Lars

On 8/4/21 7:27 PM, Mark Payne wrote:

thank you very much for your quick response. That totally explains it. I will make sure to define an upper bound, then.

Lars,

That’s interesting. The code that computes that is simple:
final MemoryUsage usage =mxBean.getNonHeapMemoryUsage();
return Ratio.of(usage.getUsed(), usage.getMax());




Thanks
-Mark

So it’s getting a MemoryUsage object from the JVM and returning usage.getUsed() / usage.getMax(). But the documentation for MemoryUsage.getMax() state that if no maximum value has been set, it will return -1. So it looks like it means the non-heap usage is really 2.81816384E8 for you. So 281 MB. And there is no max value set.

On Aug 4, 2021, at 1:19 PM, Lars Winderling <lars.winderl...@posteo.de <mailto:lars.winderl...@posteo.de>> wrote:

Dear community,



  "jvm_heap_used" : 4.26262096E8,
  "jvm_heap_usage" : 0.2646583418051402,
*  "jvm_non_heap_usage" : -2.81816384E8,*


Thanks in advance for your support!

Best,
Lars

using the QueryNiFiReportingTask on NiFi:1.13.2 on java:8, debian:10, with G1 enabled as GC, I see something like this: The non heap usage is negative by large. What does that mean? I can't seem to find any resources on the web, nor in the sources.

OpenPGP_signature
Description: OpenPGP digital signature