Adding Baseframework of the ResourceManager (all hooks and observers) are being put in place with a…

athena/resource_manager/delegate/resource_manager_delegate.cc

+// Copyright 2014 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 "athena/resource_manager/public/resource_manager_delegate.h"
+
+#include <string>
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "base/process/process_metrics.h"
+
+namespace athena {
+
+namespace {
+// This is the minimum amount of time in milliseconds between checks for
+// memory pressure.
+const int kMemoryPressureIntervalMs = 750;
+}  // namespace
+
+class ResourceManagerDelegateImpl : public ResourceManagerDelegate {
+ public:
+  ResourceManagerDelegateImpl() {}
+  virtual ~ResourceManagerDelegateImpl() {}
+
+ private:
+  virtual int GetUsedMemoryInPercent() OVERRIDE {
+    base::SystemMemoryInfoKB memory;
+    if (base::GetSystemMemoryInfo(&memory) &&
+        memory.total > 0 && memory.free >= 0) {
+      return ((memory.total - memory.free) * 100) / memory.total;

[Luigi Semenzato, 2014/08/27 21:24:08]

Is memory.free the same as the MemFree field of /proc/meminfo?  I thought we
discussed this.  That number is not particularly useful for your purposes.

[Mr4D (OOO till 08-26), 2014/08/27 22:34:01]

Okay, I will change that in a separate patch. Let's discuss what to use (somehow
I was under the impression that I should use /proc/meminfo).

+    }
+    LOG(WARNING) << "Cannot determine the free memory of the system.";
+    return 0;
+  }
+
+  virtual int MemoryPressureIntervalInMS() OVERRIDE {
+    return kMemoryPressureIntervalMs;
+  }
+  DISALLOW_COPY_AND_ASSIGN(ResourceManagerDelegateImpl);
+};
+
+// static
+ResourceManagerDelegate*
+ResourceManagerDelegate::CreateResourceManagerDelegate() {
+  return new ResourceManagerDelegateImpl;
+}
+
+}  // namespace athena