[GHC] #13110: GHC API allocates memory which is never GC'd

[GHC]

#13110: GHC API allocates memory which is never GC'd
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        Reporter:  DanielG           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHC API           |              Version:  8.0.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by DanielG):

 I just tried with master (c7297342a4) and the ghc-8.2 branch (befd937353)
 and I can still reproduce this. As I said above resetting the string table
 doesn't seem to improve the steady state memory usage at all.

 I made the test case a little easier to use and I'm including the patch I
 used to expose the `string_table`. With `ghc-expose-string-table.patch`
 applied you can reproduce this in a GHC source tree like so:

 {{{
 $ ./inplace/bin/ghc-stage2 -package ghc LeakyResetStringTable2.hs -rtsopts
 -with-rtsopts=-T
 $ ./LeakyResetStringTable
 gcdetails_live (MB): 0.443450927734375
 gcdetails_mem_in_use (MB): 81.0
 VmData (MB): 246.2578125
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13110#comment:10>
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