On Wed, Apr 18, 2018 at 11:50 AM, Andres Freund <andres@anarazel.de> wrote:
> JIT has cost, and sometimes it's not beneficial. Here our heuristics
> when to JIT appear to be a bit off. In the parallel world it's worse
> because the JITing is duplicated for parallel workers atm.
It seems like you're describing it as if the JIT just didn't produce
gains sufficient to make up for the cost of doing it, but that's not
really the issue here AFAICS. Here the JIT actually made code that
run slower than the un-JIT-ted code. That seems like a different sort
of problem.
--
Robert Haas
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