[GHC] #8027: Adding one call to getNumCapabilities triggers performance nose dive (6X slowdown)

[GHC]

#8027: Adding one call to getNumCapabilities triggers performance nose dive (6X
slowdown)
---------------------------------+------------------------------------------
    Reporter:  rrnewton          |       Owner:                         
        Type:  bug               |      Status:  new                    
    Priority:  normal            |   Milestone:                         
   Component:  Runtime System    |     Version:  7.6.3                  
    Keywords:                    |          Os:  Unknown/Multiple       
Architecture:  Unknown/Multiple  |     Failure:  Runtime performance bug
  Difficulty:  Unknown           |    Testcase:                         
   Blockedby:                    |    Blocking:                         
     Related:                    |  
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Comment(by rrnewton):

 Replying to [comment:3 rrnewton]:
 > (I'm trying to run with 7.7.20130628 but having trouble installing the
 vector package at this moment...)
 >

 By the way, I'm continuing to update the reproducer -- to get it working
 with 7.7 and to shrink it further -- on the "ghcbug" branch of this
 repository:

    https://github.com/iu-parfunc/lvars/tree/ghcbug

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/8027#comment:4>
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