#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 carter): Very cool work! Do we want to limit the number of capabilities to the number of hyper threaded cores or the number of physical cores? Likewise, another opportunity for improvement might be seeing about making sure the capabilities (when CPU pining is enabled for the rts) are spread out maximally across the available CPU cores? I believe this or a similar issue was discussed / observed by Ryan Yates / fryguybob previously but I'm not sure if we had worked out a portable way to decide this or not -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9221#comment:60 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler