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rdicosmo / parmap

Parmap is a minimalistic library allowing to exploit multicore architecture for OCaml programs with minimal modifications.
http://rdicosmo.github.io/parmap/
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round up #47

Closed JuliaLawall closed 5 years ago

JuliaLawall commented 8 years ago

It seems that parmap rounds down when statically distributing tasks to cores. For example, I have 284 tasks and 48 cores, which gives 47 cores with 5 tasks each and one core with 49. This represents a pretty massive hit on the benefits of parallelism. Giving 6 tasks to most cores would be a big performance improvement. Everything is fine with ~chunksize:1, but the need for this may not be obvious to most users.

UnixJunkie commented 7 years ago

I think chunksize=1 should be the default

UnixJunkie commented 7 years ago

everybody wants automatic load balancing to be the default. People who know which chunksize to use should really know what they are doing.

UnixJunkie commented 6 years ago

I think most users would benefit from this small little change

UnixJunkie commented 5 years ago

I am closing this because there is a workaround. But I agree that the current behavior is sub optimal. It would have been nice if there was a pull request to implement the suggested change.