[GHC] #13830: '+RTS -s' gives incorrect value for work balance in some cases

[GHC]

#13830: '+RTS -s' gives incorrect value for work balance in some cases
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        Reporter:  duog              |                Owner:  duog
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Runtime System    |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Debugging         |  Unknown/Multiple
  information is incorrect           |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3658
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"7c9e356de1114ab3e31f2d6d03e83672076dd533/ghc"
 7c9e356d/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="7c9e356de1114ab3e31f2d6d03e83672076dd533"
 Fix Work Balance computation in RTS stats

 An additional stat is tracked per gc: par_balanced_copied This is the
 the number of bytes copied by each gc thread under the balanced lmit,
 which is simply (copied_bytes / num_gc_threads).  The stat is added to
 all the appropriate GC structures, so is visible in the eventlog and in
 GHC.Stats.

 A note is added explaining how work balance is computed.

 Remove some end of line whitespace

 Test Plan:
 ./validate
 experiment with the program attached to the ticket
 examine code changes carefully

 Reviewers: simonmar, austin, hvr, bgamari, erikd

 Reviewed By: simonmar

 Subscribers: Phyx, rwbarton, thomie

 GHC Trac Issues: #13830

 Differential Revision: https://phabricator.haskell.org/D3658
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13830#comment:5>
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