[GHC] #13492: -p option report much less time than actual on high intensity of FFI calls application

[GHC]

#13492: -p option report much less time than actual on high intensity of FFI calls
application
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        Reporter:  varosi            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Profiling         |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Windows           |         Architecture:  x86_64
 Type of failure:  Debugging         |  (amd64)
  information is incorrect           |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by osa1):

 * cc: simonmar, osa1 (added)
 * version:  8.0.2 => 8.5


Comment:

 I recently needed this and ended up using event logs as profiler did not
 help because of this issue. Unfortunately event logs also have its
 problems (e.g. can't load events for a few minutes because ghc-events
 requires more than 32G RAM for that...), so this feature would still be
 useful. See also the recent Haskell-cafe questions on this
 [https://mail.haskell.org/pipermail/haskell-cafe/2018-August/129818.html
 here] and my response [https://mail.haskell.org/pipermail/haskell-
 cafe/2018-August/129820.html here].

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13492#comment:3>
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