[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)
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  Reporter:  rrnewton                 |          Owner:                  
      Type:  bug                      |         Status:  closed          
  Priority:  normal                   |      Milestone:                  
 Component:  Runtime System           |        Version:  7.6.3           
Resolution:  wontfix                  |       Keywords:                  
        Os:  Unknown/Multiple         |   Architecture:  Unknown/Multiple
   Failure:  Runtime performance bug  |     Difficulty:  Unknown         
  Testcase:                           |      Blockedby:                  
  Blocking:                           |        Related:                  
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Comment(by ezyang):

 He isn't referring to getNumCapabilities getting inlined; he's referring
 to the parReadNats function, which is polymorphic over Num instances.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/8027#comment:9>
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