RFR: 8241585: Remove unused _recursion_counter facility from PerfTraceTime

[Chris Plummer]

On 3/26/20 4:36 PM, David Holmes wrote:
> Hi Claes,
>
> Adding serviceability as they are the consumers of this IIUC.
>
> On 27/03/2020 3:40 am, Claes Redestad wrote:
>> Hi,
>>
>> PerfTraceTime::_recursion_counter is unused, and removing it
>> gets rid of some branchy (but well-predicted) code in paths that is
>> somewhat startup sensitive.
>
> Okay.
>
>> http://cr.openjdk.java.net/~redestad/8241585/open.00/
>>
>> Also added some trace logging to determine the number of perf
>> data counter or each type along with a tune-up to exactly match
>> the defaults.
>
> Okay so can you change the bug synopsis and description to cover this 
> more general cleanup and tuneup please.
>
> I'm never very clear on the uses of these PerfCounters. It seems 
> SUN_NS is unused after this change. The references to jvmstat seem no 
> longer correct - these are read via jstat ?
jstat uses jvmstat.

Chris
>
>> Testing: tier1+2
>
> I think serviceability testing is mainly in tier3.
>
> Thanks,
> David
> -----
>
>>
>> Thanks!
>>
>> /Claes