RFR (S) 8212988: add recent class unloading events to the hs_err log

[coleen.phillimore at oracle.com]

On 2/12/19 10:46 AM, Harold Seigel wrote:
> Hi Coleen,
>
> In src/hotspot/share/utilities/events.cpp, 
> UnloadingEventLog::log(...), why do you call ik->name() instead of 
> ik->external_name() ?

ik->external_name() allocates and writes into a resource array, then 
also changes '/' to '.'.  For this logging, which is always on, my 
performance testing showed that this was too expensive.

I chose name()->print_value_on(stringStream) to print the characters 
straight into the allocated buffer.

Thanks,
Coleen
>
> Thanks, Harold
>
> On 2/12/2019 10:18 AM, coleen.phillimore at oracle.com wrote:
>> Summary: also moved class unloading logging in expected place.
>>
>> Tested with assert to verify hs_err_file, some dacapo performance 
>> testing, and hs tier1-6.  See bug for details.
>>
>> open webrev at 
>> http://cr.openjdk.java.net/~coleenp/2019/8212988.01/webrev
>> bug link https://bugs.openjdk.java.net/browse/JDK-8212988
>>
>> Thanks,
>> Coleen