#11054: GHC on Windows could not use more than 64 logical processors -------------------------------------+------------------------------------- Reporter: varosi | Owner: Phyx- Type: feature request | Status: patch Priority: normal | Milestone: Component: Runtime System | Version: 7.10.2 Resolution: | Keywords: Operating System: Windows | Architecture: x86_64 Type of failure: Runtime | (amd64) performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #12602 | Differential Rev(s): Phab:D2533 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Phyx-): I accidentally build the one without NUMA support, however you shouldn't need it to be able to use all the cores. The NUMA support in GHC is limited to 16 NUMA nodes atm. Did you also specify -qa? without the scheduler doesn't do much unless you're doing setting the affinity manually in code? so `+RTS -N -qa`. If that still doesn't work then could you compile your program with `-debug` and run with `-Ds` and pipe this output to a file. just a few seconds is enough. This will help me see what the scheduler is doing. You can also use this to see how many cores it detected and in what configuration. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11054#comment:24 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler