JEP draft: Scope Locals

[Andrew Haley]

On 5/19/21 10:51 PM, David Lloyd wrote:
> I think it would be really nice if the snapshot class could hold its
> run/call method rather than making it a static method of `ScopeLocal`. This
> reads more naturally to me (and is nicer to write):

True, but inheritance is *extremely* time-critical when creating a
ForkJoin task. In many cases there won't be any scope locals to inherit,
and by allowing null snapshots you save a significant fraction of a
nanosecond when creating one. And I know, this is hard to believe, but
such an overhead has a significant macroscopic effect on benchmarks.

However, I do intend to fix this in a different way, if I can.

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