1. 11 2月, 2006 2 次提交
    • N
      [PATCH] sched: remove smpnice · a2000572
      Nick Piggin 提交于
      I don't think the code is quite ready, which is why I asked for Peter's
      additions to also be merged before I acked it (although it turned out that
      it still isn't quite ready with his additions either).
      
      Basically I have had similar observations to Suresh in that it does not
      play nicely with the rest of the balancing infrastructure (and raised
      similar concerns in my review).
      
      The samples (group of 4) I got for "maximum recorded imbalance" on a 2x2
      SMP+HT Xeon are as follows:
      
                  | Following boot | hackbench 20        | hackbench 40
       -----------+----------------+---------------------+---------------------
       2.6.16-rc2 | 30,37,100,112  | 5600,5530,6020,6090 | 6390,7090,8760,8470
       +nosmpnice |  3, 2,  4,  2  |   28, 150, 294, 132 |  348, 348, 294, 347
      
      Hackbench raw performance is down around 15% with smpnice (but that in
      itself isn't a huge deal because it is just a benchmark).  However, the
      samples show that the imbalance passed into move_tasks is increased by
      about a factor of 10-30.  I think this would also go some way to explaining
      latency blips turning up in the balancing code (though I haven't actually
      measured that).
      
      We'll probably have to revert this in the SUSE kernel.
      
      Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Cc: Peter Williams <pwil3058@bigpond.net.au>
      Cc: "Martin J. Bligh" <mbligh@aracnet.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      a2000572
    • L
      4b0955a6
  2. 10 2月, 2006 20 次提交
  3. 09 2月, 2006 18 次提交