RFR: 8255984: Shenandoah: "adaptive" heuristic is prone to missing load spikes [v3]

earthling-amzn github.com+71722661+earthling-amzn at openjdk.java.net
Fri Nov 20 01:41:05 UTC 2020

On Thu, 19 Nov 2020 19:36:12 GMT, earthling-amzn <github.com+71722661+earthling-amzn at openjdk.org> wrote:

>> Ah, it says this at the actions link:
>>>Workflows aren’t being run on this forked repository
>> Because this repository contained workflow files when it was forked, we have disabled them from running on this fork. Make sure you understand the configured workflows and their expected usage before enabling Actions on this repository.
>> I've re-enabled them and the pre-submit action is running now.
> I'm also running my own test suite (heapotheysis/HyperAlloc) with different permutations for the margin of error, spike threshold and sample frequency. I'll run the whole thing again without any headroom buffer. Will have the results by end of day.

Finished running more tests. My preference is still to keep the headroom/penalties in place. It can run without these, but there is a modest increase in degenerated cycles. If we did remove these safeguards, I'd recommend increasing the default sample frequency to 100hz.


PR: https://git.openjdk.java.net/jdk/pull/1099

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