[GHC] #9809: Overwhelming the TimerManager

[GHC]

#9809: Overwhelming the TimerManager
-------------------------------------+-------------------------------------
        Reporter:  fryguybob         |                   Owner:  simonmar
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Runtime System    |                 Version:  7.9
      Resolution:                    |                Keywords:
Operating System:  Linux             |            Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
-------------------------------------+-------------------------------------

Comment (by davean):

 Confirming this still occurs on 7.10.1.

 {{{
 $ ./Main -f +RTS -s
    3,260,792,712 bytes allocated in the heap
    3,797,542,040 bytes copied during GC
      103,056,944 bytes maximum residency (88 sample(s))
       11,062,480 bytes maximum slop
              309 MB total memory in use (0 MB lost due to fragmentation)

                                      Tot time (elapsed)  Avg pause  Max
 pause
   Gen  0      5589 colls,     0 par    0.164s   0.160s     0.0000s
 0.0004s
   Gen  1        88 colls,     0 par    1.844s   1.909s     0.0217s
 0.0656s

   TASKS: 4 (1 bound, 3 peak workers (3 total), using -N1)

   SPARKS: 0 (0 converted, 0 overflowed, 0 dud, 0 GC'd, 0 fizzled)

   INIT    time    0.000s  (  0.000s elapsed)
   MUT     time    0.220s  (  0.266s elapsed)
   GC      time    2.008s  (  2.069s elapsed)
   EXIT    time    0.000s  (  0.000s elapsed)
   Total   time    2.228s  (  2.335s elapsed)

   Alloc rate    14,821,785,054 bytes per MUT second

   Productivity   9.9% of total user, 9.4% of total elapsed

 gc_alloc_block_sync: 0
 whitehole_spin: 0
 gen[0].sync: 0
 gen[1].sync: 0
 }}}

 {{{
 ./Main +RTS -s
      182,472,160 bytes allocated in the heap
       35,704,856 bytes copied during GC
        3,270,336 bytes maximum residency (7 sample(s))
           89,368 bytes maximum slop
                8 MB total memory in use (0 MB lost due to fragmentation)

                                      Tot time (elapsed)  Avg pause  Max
 pause
   Gen  0       349 colls,     0 par    0.020s   0.016s     0.0000s
 0.0002s
   Gen  1         7 colls,     0 par    0.000s   0.008s     0.0011s
 0.0020s

   TASKS: 4 (1 bound, 3 peak workers (3 total), using -N1)

   SPARKS: 0 (0 converted, 0 overflowed, 0 dud, 0 GC'd, 0 fizzled)

   INIT    time    0.000s  (  0.000s elapsed)
   MUT     time    0.112s  (  0.152s elapsed)
   GC      time    0.020s  (  0.024s elapsed)
   EXIT    time    0.000s  (  0.000s elapsed)
   Total   time    0.132s  (  0.177s elapsed)

   Alloc rate    1,629,215,714 bytes per MUT second

   Productivity  84.8% of total user, 63.4% of total elapsed

 gc_alloc_block_sync: 0
 whitehole_spin: 0
 gen[0].sync: 0
 gen[1].sync: 0
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9809#comment:4>
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