SV: SV: JMC-5596: Rule to detect if there has been a Full GC with G1 or CMS

Andrew Azores aazores at
Thu Dec 13 17:32:08 UTC 2018

On 2018-12-12 3:30 p.m., Andrew Azores wrote:
> Hi Marcus,
> On 2018-12-12 7:43 a.m., Marcus Hirt wrote:
>> Hi Andrew,
>> There are, sadly, no official guidelines for adding recordings.
>> That said, try to:
>> 1. Keep the recording small, e.g. make the recording as short as 
>> possible,
>>     use a template where some unrelated events are disabled (take care,
>>     some events are more or less expected, e.g. Flight Recorder meta 
>> events).
>> 2. Look through the data to ensure it doesn't contain something you 
>> don't want
>>     to share. For example, it's all too easy to get a password or 
>> password hash
>>     in the environment variable or system property events.
>> Kind regards,
>> Marcus
> Thanks for the tips. I have attached another updated patch. This one now 
> includes two flight recordings, exercising the "Full GCs occurred" paths 
> for the rule for both G1 and CMS scenarios, as well as an updated test 
> baseline for the expected result reports for these recordings. I 
> disabled nearly all event types and ran the recording for as little time 
> as I was easily able to get the reproducer applet I had prepared to 
> produce full collections. If the recordings are still too large then I'm 
> sure I can make my applet hungrier for memory and get the desired events 
> to occur even sooner, which should cut down on the total number of 
> events in the recording.

This got stuck in the moderation queue due to the large size of the 
patch, so with Mario's help I have uploaded the patch instead as a 
webrev. Available here:

Andrew Azores
Software Engineer, OpenJDK Team
Red Hat

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