#10800: vector-0.11 compile time increased substantially with 7.10.1 -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: highest | Milestone: 8.0.1 Component: Compiler | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by erikd): Much like for [comment:12 comment 12], set myself up so I could build the vector test suite with ghc versions 7.8.4, 7.10.3 and 8.0.0.20160316 and then with each compiler ran `cabal clean && time cabal test` a number of times with each. This is the result of a single run, but is representative of this test: {{{ Compiler real user sys 7.8.4 1m38.167s 2m03.336s 0m43.800s 7.10.3 8m59.597s 11m40.756s 5m37.828s 8.0.0 0m45.165s 1m0.148s 0m23.744s }}} The 8.0 compiler has not only fixed the compile regression from 7.8 to 7.10, its actually about twice as fast as 7.8. Just as validation I also timed the runtime of the test suites compiled by each of the three compile and there didn't seem to be any measurable difference in run time performance. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10800#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler