[GHC] #4951: Performance regression 7.0.1 -> 7.0.1.20110201

[GHC]

#4951: Performance regression 7.0.1 -> 7.0.1.20110201
--------------------------------------+-------------------------------------
  Reporter:  simonmar                 |          Owner:  simonpj         
      Type:  bug                      |         Status:  new             
  Priority:  highest                  |      Milestone:  7.0.2           
 Component:  Compiler                 |        Version:  7.0.1           
Resolution:                           |       Keywords:                  
  Testcase:                           |      Blockedby:                  
Difficulty:                           |             Os:  Unknown/Multiple
  Blocking:                           |   Architecture:  Unknown/Multiple
   Failure:  Runtime performance bug  |  
--------------------------------------+-------------------------------------

Comment(by simonmar):

 nofib run today, comparing 7.0.1 and 7.0.1.20110210:

 {{{
 --------------------------------------------------------------------------------
         Program           Size    Allocs   Runtime   Elapsed
 --------------------------------------------------------------------------------
             Min          +0.4%     -4.4%     -2.9%     -2.9%
             Max          +7.9%   +110.8%    +65.9%    +66.7%
  Geometric Mean          +3.1%    +10.3%     +3.6%     +3.5%
 }}}

 clearly this is quite bad, we shouldn't roll 7.0.2 yet.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4951#comment:4>
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