#9476: Implement late lambda-lifting -------------------------------------+------------------------------------- Reporter: simonpj | Owner: sgraf Type: feature request | Status: closed Priority: normal | Milestone: 8.8.1 Component: Compiler | Version: 7.8.2 Resolution: fixed | Keywords: LateLamLift Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #8763 #13286 | Differential Rev(s): Phab:D5224 Wiki Page: LateLamLift | -------------------------------------+------------------------------------- Comment (by simonpj): Interesting. The fact that this program has a tiny inner loop makes it feasibly to dig into. If I were doing this, I think the next thing I'd try would be to histogram the heap contents (info-pointer, number of closures with that info pointer) at each GC. This is roughly want heap profiling can do, but it may collapse too many things into one. More ambitiously, the heap profiler is supposed to be able to plot "lag"; that is, stuff that is kept alive, but is never subsequently referenced. If that is still working it'd be interesting to know whether or not the extra residency is hanging onto stuff that is never subsequently referenced. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9476#comment:61 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler