#11666: Severe performance degradation in GHC 8.0.1 compared to GHC 7.10.x -------------------------------------+------------------------------------- Reporter: mrkkrp | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1-rc2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by mrkkrp): I will try to find time and profile tomorrow to find out what is taking so long. This package is quite fast with 7.10.3, just as fast as `zip` and `unzip` utilities. I think it's because of zlib bindings and conduits used. Just a wild guess: conduit uses rewrite rules and fusion, maybe something of this behaves differently with the new version of compiler? This is just an idea, I'm not an expert in this area. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11666#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler