Re:JIT and Ruby's MJIT
by ShroudedNight on Friday December 06, 2019 @08:54PM
(#21727931)
>> MJIT will slow Rails down instead of speeding it up.
>> That’s a pretty significant footnote.
> Oops.
FWIW / from what I remember, generating high-performance native code for Rails was hard (or at least significantly different from optimizing standard benchmark type code). The OMR JIT for Ruby had similar challenges, with at least a few 'at least we didn't make it worse' moments.
I was only tangentially involved, but I vaguely recall Rails needing (or at least appearing to need) a lot more inlining and string manipulation optimizations to fly.
>> That’s a pretty significant footnote.
> Oops.
FWIW / from what I remember, generating high-performance native code for Rails was hard (or at least significantly different from optimizing standard benchmark type code). The OMR JIT for Ruby had similar challenges, with at least a few 'at least we didn't make it worse' moments.
I was only tangentially involved, but I vaguely recall Rails needing (or at least appearing to need) a lot more inlining and string manipulation optimizations to fly.