[GHC] #7850: Strangely high memory usage on optimized Ackermann function

[GHC]

#7850: Strangely high memory usage on optimized Ackermann function
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    Reporter:  dolio             |       Owner:                         
        Type:  bug               |      Status:  new                    
    Priority:  normal            |   Milestone:                         
   Component:  Compiler          |     Version:  7.6.2                  
    Keywords:                    |          Os:  Unknown/Multiple       
Architecture:  Unknown/Multiple  |     Failure:  Runtime performance bug
  Difficulty:  Unknown           |    Testcase:                         
   Blockedby:                    |    Blocking:                         
     Related:                    |  
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Comment(by awson):

 Replying to [comment:25 refold]:
 > Replying to [comment:24 awson]:
 > > Most interesting is that while many notice `-kc1M` cure the problem
 they still insist it runs much slower than Ocaml version. But it is *NOT*!
 >
 > Interesting to hear about this difference between platforms. On Linux
 (and apparently OS X) it just eats all memory and does not finish.

 AFAIU on Linux and OS X `-kc1M` on 7.6.x makes memory consumption very
 good, but performance is still several times worse than that of Ocaml both
 for 7.6.x with `-kc1M` and HEAD (where this bug is declared to be fixed).

 Still, the performance is *several times* better under Windows for 7.6.x
 (sadly, there are no HEAD builds for Windows to try).

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7850#comment:26>
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