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What's the status of multicore programming in Haskell?
What is the status especially in GHC? Is it popular yet, or still being experimental?
How careful/fine-grained is the compiler in deciding when and how to parallelize? Does the run-time choose the threadpool's size appropriately or we have to specify through command line?
GHC's current scheduling, thread pool and migration policies are described in the paper "Runtime Support for Multicore Haskell". The "strategies" style semi-automatic parallelism is quite widely used, at the time of writing.