[GHC] #8224: Excessive system time -- new IO manager problem?

[GHC]

#8224: Excessive system time -- new IO manager problem?
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        Reporter:  rrnewton          |            Owner:
            Type:  bug               |           Status:  new
        Priority:  high              |        Milestone:  7.8.1
       Component:  Runtime System    |          Version:  7.7
      Resolution:                    |         Keywords:  IO Manager,
Operating System:  Linux             |  System Time
 Type of failure:  Runtime           |     Architecture:  x86_64 (amd64)
  performance bug                    |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by AndreasVoellmy):

 Actually, I can simplify the program to just
 {{{
 main = return ()
 }}}
 and I get 200ms in kernel when run with -N32. I'm not sure how significant
 this 200ms time is - I guess it is time spent initializing or cleaning up
 capabilities (possibly including IO manager resources).

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8224#comment:6>
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