#9221: (super!) linear slowdown of parallel builds on 40 core machine -------------------------------------+------------------------------------- Reporter: carter | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 7.8.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #910, #8224 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonmar): With a very large `-A` like that you probably want to use nursery chunks: `-n4m`. It's also worth playing with `-qn`, e.g. on the 12x2 Haswell I suggest `-N24 -A128m -n4m -qn12` should work well. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9221#comment:72 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler