RFR: 8241585: Remove unused _recursion_counter facility from PerfTraceTime

[David Holmes]

On 27/03/2020 9:46 am, Chris Plummer wrote:
> 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.

Thanks Chris, I was grepping C++ code not realizing jvmstat is a Java API.

David

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