RFR (S): 8136679: JFR Event for adaptive IHOP

Mikael Gerdin mikael.gerdin at oracle.com
Tue Nov 24 09:36:07 UTC 2015


Hi Thomas,

On 2015-11-19 12:02, Thomas Schatzl wrote:
> Hi Tom,
>
> On Wed, 2015-11-18 at 17:34 -0500, Tom Benson wrote:
>> Hi Thomas,
>> In g1IHOPControl.cpp, the call to report_basic_ihop_statistics at line
>> 198 in G1AdaptiveIHOPControl::send_event passes
>> _allocation_rate_s.last() for the last_allocation_duration argument.
>> Looking at your other IHOP change, I think it actually is a rate, rather
>> than a duration, so perhaps not what you want here. ?
>>
>> I also noticed an extra-trivial typo in trace.xml: "since last GC in
>> bytes/seconds"should be /second.
>>
>> Looks fine otherwise.
>
> It contains much more changes than you'd expect because the first issue
> nudged me to move some duplicated code into the base class.
>
> It also contains changes suggested by the perf team that improve the JFR
> event specific to adaptive IHOP to also pass a IHOP threshold percentage
> relative to the internal IHOP target occupancy, not only relative to the
> total heap size.
>
> Fixed in
> http://cr.openjdk.java.net/~tschatzl/8136679/webrev.1_to_2
> http://cr.openjdk.java.net/~tschatzl/8136679/webrev.2 (full)

Looks good to me.
/Mikael

>
> Thanks,
>    Thomas
>
>
>



More information about the hotspot-gc-dev mailing list