#15999: Stabilise nofib runtime measurements -------------------------------------+------------------------------------- Reporter: sgraf | Owner: (none) Type: task | Status: new Priority: normal | Milestone: ⊥ Component: NoFib benchmark | Version: 8.6.2 suite | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #5793 #9476 | Differential Rev(s): Phab:D5438 #15333 #15357 | Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonmar): So as I understand it, the GC "wibbles" you're talking about are caused by the number of GCs we run? Making a small change to the nursery size can make the difference between N and N+1 GC runs, which could be a large difference in runtime. You're only looking at `-G1`, right? Generational GC often has weird effects based on the timing of when a GC runs. I think there will still be issues when there's an old-gen collection right around the end of the program run - making a small change may mean the difference between running or not running the expensive GC. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15999#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler