Re: How long does AppD take to perform Garbage Collection analysis

CommunityUser — Tue, 09 Oct 2018 23:10:20 GMT

Hi Brian,

Thank you so much for your info. Sorry I will give you more clarification on my request.

Usually when you look at Garbage collection performance, Log anysis tool

such as GC log analyser gives you additional metrics to help fine tune GC performance.

Common metric used is "GC Duration".

GC Duration values reported contains

1 "GC Pause Duration"

2. "GC concurrent Duration"

"GC Pause Duration" is valuable metric to monitor that often needs tuning. Some GC log analysers are able to extract "GC Pause Duration".

Just wondering AppD capability to provide "GC pause duration"!

Definitions:

Pending on event type (Fully paused or Partiall Paused)

Young GC : Fully paused (GC Duration = GC Pause Duration)

Old GC : Partially Paused (out of 5 phases: 3-complelely paused[GC Pause Duration] & 2-run

concurrently[GC concurrent Duration]

Let me know your thougts.

Many Thanks

Adrian

Re: How long does AppD take to perform Garbage Collection analysis

Brian_Wheeldon — Wed, 10 Oct 2018 12:52:24 GMT

Thanks for the clarification Adrian.

The Java agent collects heap, memory, and GC-related metrics from standard JMX MBeans in the instrumented JVM. These metrics are available whether or not verbose GC logging is enabled.

This means that the agent does not have access to the verbose GC logs and does not analyze these logs to calculate "GC Pause Duration" or "GC concurrent Duration".

The agent does provide metrics for "Garbage Collection Time Spent (ms/min)" broken down by "Minor Collections", "Major Collections", and "Total".

I believe that these metrics should be helpful for fine tuning the GC performance, with less overhead and effort than generating verbose GC logs and running a GC log analyzer on these logs.

Screenshot of the JVM Memory page attached.

Regards,

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Re: How long does AppD take to perform Garbage Collection analysis

Re: How long does AppD take to perform Garbage Collection analysis