)]}'
{
  "commit": "24cf72518c79cdcda486ed26074ff8151291cf65",
  "tree": "0db04965fb57135e68edf62c332c3a3825c1e3b5",
  "parents": [
    "fa5e084e43eb14c14942027e1e2e894aeed96097"
  ],
  "author": {
    "name": "Mel Gorman",
    "email": "mel@csn.ul.ie",
    "time": "Tue Jun 16 15:33:23 2009 -0700"
  },
  "committer": {
    "name": "Linus Torvalds",
    "email": "torvalds@linux-foundation.org",
    "time": "Tue Jun 16 19:47:46 2009 -0700"
  },
  "message": "vmscan: count the number of times zone_reclaim() scans and fails\n\nOn NUMA machines, the administrator can configure zone_reclaim_mode that\nis a more targetted form of direct reclaim.  On machines with large NUMA\ndistances for example, a zone_reclaim_mode defaults to 1 meaning that\nclean unmapped pages will be reclaimed if the zone watermarks are not\nbeing met.\n\nThere is a heuristic that determines if the scan is worthwhile but it is\npossible that the heuristic will fail and the CPU gets tied up scanning\nuselessly.  Detecting the situation requires some guesswork and\nexperimentation so this patch adds a counter \"zreclaim_failed\" to\n/proc/vmstat.  If during high CPU utilisation this counter is increasing\nrapidly, then the resolution to the problem may be to set\n/proc/sys/vm/zone_reclaim_mode to 0.\n\n[akpm@linux-foundation.org: name things consistently]\nSigned-off-by: Mel Gorman \u003cmel@csn.ul.ie\u003e\nReviewed-by: Rik van Riel \u003criel@redhat.com\u003e\nCc: Christoph Lameter \u003ccl@linux-foundation.org\u003e\nReviewed-by: KOSAKI Motohiro \u003ckosaki.motohiro@jp.fujitsu.com\u003e\nCc: Wu Fengguang \u003cfengguang.wu@intel.com\u003e\nCc: \u003cstable@kernel.org\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": "ff4696c6dce3f84eebcf109cd6a6d721e02097d6",
      "old_mode": 33188,
      "old_path": "include/linux/vmstat.h",
      "new_id": "81a97cf8f0a0845a102a1200dc316aa32a47920f",
      "new_mode": 33188,
      "new_path": "include/linux/vmstat.h"
    },
    {
      "type": "modify",
      "old_id": "16c82a868e2b293c2533335f5881412ffee404d8",
      "old_mode": 33188,
      "old_path": "mm/vmscan.c",
      "new_id": "3018ad75613375c409f6a99d2e2a105604833c81",
      "new_mode": 33188,
      "new_path": "mm/vmscan.c"
    },
    {
      "type": "modify",
      "old_id": "1e3aa8139f22a27f72e688c8953cba04b7a9cded",
      "old_mode": 33188,
      "old_path": "mm/vmstat.c",
      "new_id": "138bed53706ed325e2d4aac3ae0065cffccdda47",
      "new_mode": 33188,
      "new_path": "mm/vmstat.c"
    }
  ]
}