#11725: Performance Regression from 7.8.3 to 7.10.3 -------------------------------------+------------------------------------- Reporter: dominic | Owner: dominic Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Resolution: | Keywords: Operating System: Linux | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by dominic): Good news! After a heroic battle fighting cabal, template-haskell, unnecessarily restrictive upper bounds and the ghc build system on OS X 10.11.3, in which the aforementioned almost won, I managed to get my test program to compile under ghc-8.0.1-rc2. Under ghc-7.10.2 (NB not comparable with the above as that was done on a different machine) I get {{{ Total time 12.764s ( 13.242s elapsed) }}} Under ghc-8.0.1-rc2 I get {{{ Total time 2.896s ( 3.290s elapsed) }}} So better even than 7.83. For info I ran my comparison of 7.8.3 against 7.10.3 on {{{ processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 63 model name : Intel(R) Xeon(R) CPU E5-2673 v3 @ 2.40GHz stepping : 2 microcode : 0xffffffff cpu MHz : 2397.169 cache size : 30720 KB physical id : 0 siblings : 1 core id : 0 cpu cores : 1 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx lm constant_tsc rep_good nopl eagerfpu pni pclmulqdq ss\ se3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm abm fsgsbase bmi1 avx2 smep bmi2 erms xsaveopt bugs : bogomips : 4794.33 clflush size : 64 cache_alignment : 64 address sizes : 42 bits physical, 48 bits virtual power management: }}} and I ran my comparison of 7.10.3 againt 8.0.1-rc2 on {{{ Intel(R) Core(TM) i7-3720QM CPU @ 2.60GHz }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11725#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler