#9630: compile-time performance regression (probably due to Generics) -------------------------------------+------------------------------------- Reporter: hvr | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.4.1 Component: Compiler | Version: 7.9 Resolution: | Keywords: deriving- | perf, Generics Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #9583, #10293, | Differential Rev(s): #13059, #10818 | Wiki Page: | -------------------------------------+------------------------------------- Changes (by dfeuer): * cc: dfeuer (added) * related: #9583, #10293, #13059 => #9583, #10293, #13059, #10818 Comment: It appears that much or all of the regression in the original example occurred in b9e49d3e9580e13d89efd1f779cb76f610e0d6e0. Before, I get {{{ dfeuer@squirrel:~/src/cabal> ~/src/ghc-iproute-before/inplace/bin/ghc- stage2 -Rghc-timing -O -c Cabal/Language/Haskell/Extension.hs <<ghc: 5795390224 bytes, 640 GCs, 37133197/104324936 avg/max bytes residency (16 samples), 248M in use, 0.001 INIT (0.001 elapsed), 3.981 MUT (4.258 elapsed), 2.622 GC (2.639 elapsed) :ghc>> }}} After, {{{ dfeuer@squirrel:~/src/cabal> ~/src/ghc-iproute-after/inplace/bin/ghc- stage2 -Rghc-timing -O -c Cabal/Language/Haskell/Extension.hs <<ghc: 126972407680 bytes, 3337 GCs, 340164097/914871104 avg/max bytes residency (36 samples), 2652M in use, 0.001 INIT (0.001 elapsed), 82.951 MUT (118.315 elapsed), 52.254 GC (52.317 elapsed) :ghc>> }}} Jeepers! -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9630#comment:40> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler