[GHC] #9675: Unreasonable memory usage on large data structures

[GHC]

#9675: Unreasonable memory usage on large data structures
-------------------------------------+-------------------------------------
              Reporter:  Polarina    |            Owner:
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.8.3
            Resolution:              |         Keywords:
      Operating System:  Linux       |     Architecture:  x86_64 (amd64)
       Type of failure:  Compile-    |       Difficulty:  Unknown
  time performance bug               |       Blocked By:
             Test Case:              |  Related Tickets:
              Blocking:              |
Differential Revisions:              |
-------------------------------------+-------------------------------------

Comment (by nomeata):

 Heap profiling tells me that most of it is retained by `dmdAnalRhs`,
 produced by `annotateBndrs/dmdAnalAlt/dmdAnal'`. But even after cluttering
 most of the module with {{{`seq`}}} and bang patterns, the leak is still
 there....

 and just while I was about to give up I found the problem: The environment
 part of a DmdType is not seq’ed. Doing that does great good. Patch
 coming.... :-)

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9675#comment:11>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler