Revert 65010 - Adding OOM priority management for renderers on ChromeOS.

Reverting because this causes problems on valgrind (for ChromeOS only).

Turns out that TabStripModel is not thread safe, and I'm calling from
another thread.

Review URL: http://codereview.chromium.org/4446002

TBR=gspencer@chromium.org
Review URL: http://codereview.chromium.org/4417006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@65091 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 0 insertions, 169 deletions

diff --git a/chrome/browser/oom_priority_manager.cc b/chrome/browser/oom_priority_manager.cc
deleted file mode 100644
index 63329cd..0000000
--- a/chrome/browser/oom_priority_manager.cc
+++ /dev/null
@@ -1,169 +0,0 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chrome/browser/oom_priority_manager.h"
-
-#include <list>
-
-#include "base/process.h"
-#include "base/process_util.h"
-#include "base/thread.h"
-#include "build/build_config.h"
-#include "chrome/browser/browser_list.h"
-#include "chrome/browser/browser_thread.h"
-#include "chrome/browser/renderer_host/render_process_host.h"
-#include "chrome/browser/tab_contents/tab_contents.h"
-#include "chrome/browser/tabs/tab_strip_model.h"
-#include "chrome/browser/zygote_host_linux.h"
-
-#if !defined(OS_CHROMEOS)
-#error This file only meant to be compiled on ChromeOS
-#endif
-
-using base::TimeDelta;
-using base::TimeTicks;
-using base::ProcessHandle;
-using base::ProcessMetrics;
-
-namespace browser {
-
-// The default interval in seconds after which to adjust the oom_adj
-// value.
-#define ADJUSTMENT_INTERVAL_SECONDS 10
-
-// The default interval in minutes for considering activation times
-// "equal".
-#define BUCKET_INTERVAL_MINUTES 10
-
-OomPriorityManager::OomPriorityManager() {
-  StartTimer();
-}
-
-OomPriorityManager::~OomPriorityManager() {
-  StopTimer();
-}
-
-void OomPriorityManager::StartTimer() {
-  if (!timer_.IsRunning()) {
-    timer_.Start(TimeDelta::FromSeconds(ADJUSTMENT_INTERVAL_SECONDS),
-                 this,
-                 &OomPriorityManager::AdjustOomPriorities);
-  }
-}
-
-void OomPriorityManager::StopTimer() {
-  timer_.Stop();
-}
-
-
-namespace {
-struct RendererStats {
-  bool is_pinned;
-  TimeTicks last_selected;
-  size_t memory_used;
-  ProcessHandle renderer_handle;
-};
-
-// Returns true if |first| is considered less desirable to be killed
-// than |second|.
-bool SortRendererStats(RendererStats first, RendererStats second) {
-  // The size of the slop in comparing activation times.  [This is
-  // allocated here to avoid static initialization at startup time.]
-  static const int64 kTimeBucketInterval =
-      TimeDelta::FromMinutes(BUCKET_INTERVAL_MINUTES).ToInternalValue();
-
-  // Being pinned is most important.
-  if (first.is_pinned != second.is_pinned)
-    return first.is_pinned == true;
-
-  // We want to be a little "fuzzy" when we compare these, because
-  // it's not really possible for the times to be identical, but if
-  // the user selected two tabs at about the same time, we still want
-  // to take the one that uses more memory.
-  if (abs((first.last_selected - second.last_selected).ToInternalValue()) <
-      kTimeBucketInterval)
-    return first.last_selected < second.last_selected;
-
-  return first.memory_used < second.memory_used;
-}
-}  // anonymous namespace
-
-// Post a new task for the file thread to actually adjust the priorities.
-void OomPriorityManager::AdjustOomPriorities() {
-  BrowserThread::PostTask(
-      BrowserThread::FILE, FROM_HERE,
-      NewRunnableMethod(this, &OomPriorityManager::DoAdjustOomPriorities));
-}
-
-// Here we collect all the information we need to sort the existing
-// renderers in priority order, and hand out oom_adj scores based on
-// that sort order.
-//
-// Things we need to collect:
-// 1) whether or not a tab is pinned
-// 2) last time a tab was selected
-// 3) size in memory of a tab
-void OomPriorityManager::DoAdjustOomPriorities() {
-  std::list<RendererStats> renderer_stats;
-
-  if (BrowserList::size() == 0)
-    return;
-
-  for (BrowserList::const_iterator browser_iterator = BrowserList::begin();
-       browser_iterator != BrowserList::end(); ++browser_iterator) {
-    Browser* browser = *browser_iterator;
-    const TabStripModel* model = browser->tabstrip_model();
-    for (int i = 0; i < model->count(); i++) {
-      TabContents* contents = model->GetTabContentsAt(i);
-      RendererStats stats;
-      stats.last_selected = contents->last_selected_time();
-      stats.renderer_handle = contents->GetRenderProcessHost()->GetHandle();
-      scoped_ptr<ProcessMetrics> metrics(
-          ProcessMetrics::CreateProcessMetrics(stats.renderer_handle));
-
-      base::WorkingSetKBytes working_set_kbytes;
-      if (metrics->GetWorkingSetKBytes(&working_set_kbytes)) {
-        // We use the proportional set size (PSS) to calculate memory
-        // usage "badness" on Linux.
-        stats.memory_used = working_set_kbytes.shared * 1024;
-      } else {
-        // and if for some reason we can't get PSS, we revert to using
-        // resident set size (RSS).
-        stats.memory_used = metrics->GetWorkingSetSize();
-      }
-
-      stats.is_pinned = model->IsTabPinned(i);
-      renderer_stats.push_back(stats);
-    }
-  }
-
-  // Now we sort the data we collected so that least desirable to be
-  // killed is first, most desirable is last.
-  renderer_stats.sort(SortRendererStats);
-
-  // Now we assign priorities based on the sorted list.  We're
-  // assigning priorities in the range of 5 to 10.  oom_adj takes
-  // values from -17 to 15.  Negative values are reserved for system
-  // processes, and we want to give some room on either side of the
-  // range we're using to allow for things that want to be above or
-  // below the renderers in priority, so 5 to 10 gives us some
-  // variation in priority without taking up the whole range.  In the
-  // end, however, it's a pretty arbitrary range to use.  Higher
-  // values are more likely to be killed by the OOM killer.
-  const int kMinPriority = 5;
-  const int kMaxPriority = 10;
-  const int kPriorityRange = kMaxPriority - kMinPriority;
-  float priority_increment =
-      static_cast<float>(kPriorityRange) / renderer_stats.size();
-  float priority = kMinPriority;
-  for (std::list<RendererStats>::iterator iterator = renderer_stats.begin();
-       iterator != renderer_stats.end(); ++iterator) {
-    Singleton<ZygoteHost>()->AdjustRendererOOMScore(
-        iterator->renderer_handle,
-        static_cast<int>(priority + 0.5f));
-    priority += priority_increment;
-  }
-}
-
-}  // namespace browser