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kares
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headius
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This all seems good to me!
I don't know what to say about eval methods; in order for them to be a problem, they'd have to:
- Be continually generated at runtime. This is very uncommon.
- Be called enough to JIT. This seems unlikely now and even more unlikely with our time-based threshold changes.
On the flip side, many methods get generated using eval in a "safe" way (only once, usually to lazily metaprogram some methods) and we definitely want those to be eligible for JIT without a whole separate classloader (when running in a shared mode).
I think we go with this for now as-is. Folks that opt into shared classloading can help us uncover any weird eval edge cases.
enebo
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Sep 26, 2019
either for every JIT-ed class or based on source file
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introduces a
-Xjit.loader.modewhich is either UNIQUE (default), SHARED or SHARED_SOURCEmost of it is making
WeakValueMapimplementMapas I originally did something else here ...so I've kept that code and just did a fake
Mapfor the single (shared) global class-loader.that can be changed as needed to a cleaner (proper oop) way.
the SHARED_SOURCE was so far only tested with jruby's test suite, the JITed class-loader count went down to 10% ... and meta-space was much less fragmented - saving around 8% of allocated space.
was not sure whether we should attempt to somehow detect
eval-ed piecesand not share them with the same source file but rather always on their own?
given that SHARED_SOURCE isn't changed to be the new default, we can also decide later.
also if you have suggestions for better naming the option or the enum values.