RFR: 8241585: Remove unused _recursion_counter facility from PerfTraceTime

[David Holmes]

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 ?

> Testing: tier1+2

I think serviceability testing is mainly in tier3.

Thanks,
David
-----

> 
> Thanks!
> 
> /Claes