RFR (S): 8204082: Make names of Young GCs more uniform in logs

[Kirk Pepperdine]

> On Jun 15, 2018, at 11:46 AM, Stefan Johansson <stefan.johansson at oracle.com> wrote:
> 
> Hi Kirk,
> 
> On 2018-06-15 08:50, Kirk Pepperdine wrote:
>> Hi Thomas,
>> From a parsing POV would be preferable "Pause Young Normal" would be preferable to Pause Young (Normal)".  I know it's a small change but it does make a difference. The rest of the code is fine (of course not an official review).
>> As for the change it's self, [73.077s][info ][gc,start     ] GC(262) Pause Initial Mark (G1 Humongous Allocation) is already perfectly clear to me. I'm not sure how
>> [73.077s][info ][gc,start     ] GC(262) Pause Young (Initial Mark)  (G1 Humongous Allocation) clarifies things. IMO, this change only adds to the already high level of noise in the GC logs. 
> I think this makes it more clear that Initial Mark is actually doing a Young GC as well as initiating the concurrent cycle and with the new proposed tags it will be even more clear IMHO.

Sure… but a GC log is really an audit trail of GC events…… when the collector ran, what the collector did, and how long it took to get the work done. In order to understand the audit trail you have to have some knowledge of how the collector works. Thus adding “Pause” and “Young” to Initial Mark is redundant to those that know and not any more helpful to those that don’t know how the collector works. And when you consider the use case for GC logs, it’s mostly going to be managed by tooling anyways.

If you decide to keep the redundant information I would still like to request that the braces be dropped.

Kind regards,
Kirk

>> On Thu, Jun 14, 2018 at 4:02 PM, Thomas Schatzl <thomas.schatzl at oracle.com <mailto:thomas.schatzl at oracle.com>> wrote:
>>    Hi all,
>>       another round of reviews after some more internal remarks :P
>>    I also changed the title of the CR.
>>    The set of "final" tags would be:
>>    Pause Young (Normal) ...
>>    Pause Young (Concurrent Start) ...
>>    Pause Young (Concurrent End) ...
>>    Pause Young (Mixed) ...
>>    I also adapted the strings in the GCVerifyType functionality.
>>    http://cr.openjdk.java.net/~tschatzl/8204082/webrev.1_to_2
>>    <http://cr.openjdk.java.net/~tschatzl/8204082/webrev.1_to_2> (diff)
>>    http://cr.openjdk.java.net/~tschatzl/8204082/webrev.2
>>    <http://cr.openjdk.java.net/~tschatzl/8204082/webrev.2> (full)
>>    Testing:
>>    running through all gc tests locally
>>    Thanks,
>>       Thomas