RFR 8231264: Disable biased-locking and deprecate all flags related to biased-locking

Andrew Haley aph at redhat.com
Wed Nov 27 13:55:14 UTC 2019


On 11/27/19 1:24 AM, John Rose wrote:
> For now, I will be glad to see us prove (by experience) that BL is no longer
> needed on today’s workloads and hardware, and can be deleted.  Current
> evidence indicates this is possible. Barring new evidence, we need to clear
> the decks here for future work.

What evidence is that? We've already heard that one of the benchmarks
quoted (SPECjbb2015) was specifically written so that locks are more
or less contended, so that locks get out of their biased state.
According to the author of the benchmark, "therefore, arguing that
biased locking is not needed because SPECjbb2015 does not show the
benefit of having it enabled -- is circular."

-- 
Andrew Haley  (he/him)
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
https://keybase.io/andrewhaley
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