)]}'
{
  "commit": "01dbe5c9b1004dab045cb7f38428258ca9cddc02",
  "tree": "526bba2afd30a7a58e47597f0ab9255a37a21d55",
  "parents": [
    "a79311c14eae4bb946a97af25f3e1b17d625985d"
  ],
  "author": {
    "name": "KOSAKI Motohiro",
    "email": "kosaki.motohiro@jp.fujitsu.com",
    "time": "Tue Jan 06 14:40:02 2009 -0800"
  },
  "committer": {
    "name": "Linus Torvalds",
    "email": "torvalds@linux-foundation.org",
    "time": "Tue Jan 06 15:59:06 2009 -0800"
  },
  "message": "vmscan: improve reclaim throughput to bail out patch\n\nThe vmscan bail out patch move nr_reclaimed variable to struct\nscan_control.  Unfortunately, indirect access can easily happen cache\nmiss.\n\nif heavy memory pressure happend, that\u0027s ok.\ncache miss already plenty. it is not observable.\n\nbut, if memory pressure is lite, performance degression is obserbable.\n\nI compared following three pattern (it was mesured 10 times each)\n\nhackbench 125 process 3000\nhackbench 130 process 3000\nhackbench 135 process 3000\n\n            2.6.28-rc6                       bail-out\n\n\t125\t130\t135\t\t125\t130\t135\n      \u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\n\t71.866\t75.86\t81.274\t\t93.414\t73.254\t193.382\n\t74.145\t78.295\t77.27\t\t74.897\t75.021\t80.17\n\t70.305\t77.643\t75.855\t\t70.134\t77.571\t79.896\n\t74.288\t73.986\t75.955\t\t77.222\t78.48\t80.619\n\t72.029\t79.947\t78.312\t\t75.128\t82.172\t79.708\n\t71.499\t77.615\t77.042\t\t74.177\t76.532\t77.306\n\t76.188\t74.471\t83.562\t\t73.839\t72.43\t79.833\n\t73.236\t75.606\t78.743\t\t76.001\t76.557\t82.726\n\t69.427\t77.271\t76.691\t\t76.236\t79.371\t103.189\n\t72.473\t76.978\t80.643\t\t69.128\t78.932\t75.736\n\navg\t72.545\t76.767\t78.534\t\t76.017\t77.03\t93.256\nstd\t1.89\t1.71\t2.41\t\t6.29\t2.79\t34.16\nmin\t69.427\t73.986\t75.855\t\t69.128\t72.43\t75.736\nmax\t76.188\t79.947\t83.562\t\t93.414\t82.172\t193.382\n\nabout 4-5% degression.\n\nThen, this patch introduces a temporary local variable.\n\nresult:\n\n            2.6.28-rc6                       this patch\n\nnum\t125\t130\t135\t\t125\t130\t135\n      \u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\n\t71.866\t75.86\t81.274\t\t67.302\t68.269\t77.161\n\t74.145\t78.295\t77.27   \t72.616\t72.712\t79.06\n\t70.305\t77.643\t75.855  \t72.475\t75.712\t77.735\n\t74.288\t73.986\t75.955  \t69.229\t73.062\t78.814\n\t72.029\t79.947\t78.312  \t71.551\t74.392\t78.564\n\t71.499\t77.615\t77.042  \t69.227\t74.31\t78.837\n\t76.188\t74.471\t83.562  \t70.759\t75.256\t76.6\n\t73.236\t75.606\t78.743  \t69.966\t76.001\t78.464\n\t69.427\t77.271\t76.691  \t69.068\t75.218\t80.321\n\t72.473\t76.978\t80.643  \t72.057\t77.151\t79.068\n\navg\t72.545\t76.767\t78.534 \t\t70.425\t74.2083\t78.462\nstd \t1.89\t1.71\t2.41    \t1.66\t2.34\t1.00\nmin \t69.427\t73.986\t75.855  \t67.302\t68.269\t76.6\nmax \t76.188\t79.947\t83.562  \t72.616\t77.151\t80.321\n\nOK. the degression is disappeared.\n\nSigned-off-by: KOSAKI Motohiro \u003ckosaki.motohiro@jp.fujitsu.com\u003e\nAcked-by: Rik van Riel \u003criel@redhat.com\u003e\nCc: Mel Gorman \u003cmel@csn.ul.ie\u003e\nSigned-off-by: Andrew Morton \u003cakpm@linux-foundation.org\u003e\nSigned-off-by: Linus Torvalds \u003ctorvalds@linux-foundation.org\u003e\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "5faa7739487f9e9da92f1e8c3a59f00cac1deb32",
      "old_mode": 33188,
      "old_path": "mm/vmscan.c",
      "new_id": "13f050d667e944c24d266bccace57c8b7b95b67c",
      "new_mode": 33188,
      "new_path": "mm/vmscan.c"
    }
  ]
}