1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
// Copyright 2013 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 "content/browser/renderer_host/renderer_frame_manager.h"
#include <algorithm>
#include "base/bind.h"
#include "base/logging.h"
#include "base/memory/memory_pressure_listener.h"
#include "base/memory/shared_memory.h"
#include "base/sys_info.h"
#include "content/common/host_shared_bitmap_manager.h"
#if defined(OS_CHROMEOS)
#include "base/chromeos/memory_pressure_observer_chromeos.h"
#include "content/browser/browser_main_loop.h"
#endif
namespace content {
namespace {
const int kModeratePressurePercentage = 50;
const int kCriticalPressurePercentage = 10;
} // namespace
RendererFrameManager* RendererFrameManager::GetInstance() {
return Singleton<RendererFrameManager>::get();
}
void RendererFrameManager::AddFrame(RendererFrameManagerClient* frame,
bool locked) {
RemoveFrame(frame);
if (locked)
locked_frames_[frame] = 1;
else
unlocked_frames_.push_front(frame);
CullUnlockedFrames(GetMaxNumberOfSavedFrames());
}
void RendererFrameManager::RemoveFrame(RendererFrameManagerClient* frame) {
std::map<RendererFrameManagerClient*, size_t>::iterator locked_iter =
locked_frames_.find(frame);
if (locked_iter != locked_frames_.end())
locked_frames_.erase(locked_iter);
unlocked_frames_.remove(frame);
}
void RendererFrameManager::LockFrame(RendererFrameManagerClient* frame) {
std::list<RendererFrameManagerClient*>::iterator unlocked_iter =
std::find(unlocked_frames_.begin(), unlocked_frames_.end(), frame);
if (unlocked_iter != unlocked_frames_.end()) {
DCHECK(locked_frames_.find(frame) == locked_frames_.end());
unlocked_frames_.remove(frame);
locked_frames_[frame] = 1;
} else {
DCHECK(locked_frames_.find(frame) != locked_frames_.end());
locked_frames_[frame]++;
}
}
void RendererFrameManager::UnlockFrame(RendererFrameManagerClient* frame) {
DCHECK(locked_frames_.find(frame) != locked_frames_.end());
size_t locked_count = locked_frames_[frame];
DCHECK(locked_count);
if (locked_count > 1) {
locked_frames_[frame]--;
} else {
RemoveFrame(frame);
unlocked_frames_.push_front(frame);
CullUnlockedFrames(GetMaxNumberOfSavedFrames());
}
}
size_t RendererFrameManager::GetMaxNumberOfSavedFrames() const {
#if defined(OS_CHROMEOS)
content::BrowserMainLoop* browser_main_loop =
content::BrowserMainLoop::GetInstance();
// Unit tests can come here without a BrowserMainLoop instance.
if (!browser_main_loop)
return max_number_of_saved_frames_;
base::MemoryPressureObserverChromeOS* observer =
browser_main_loop->memory_pressure_observer();
if (!observer)
return max_number_of_saved_frames_;
// Until we have a global OnMemoryPressureChanged event we need to query the
// value from our specific pressure observer.
int percentage = 100;
switch (observer->GetCurrentPressureLevel()) {
case base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE:
percentage = 100;
break;
case base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_MODERATE:
percentage = kModeratePressurePercentage;
break;
case base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_CRITICAL:
percentage = kCriticalPressurePercentage;
break;
}
size_t frames = (max_number_of_saved_frames_ * percentage) / 100;
return std::max(static_cast<size_t>(1), frames);
#else
return max_number_of_saved_frames_;
#endif
}
RendererFrameManager::RendererFrameManager()
: memory_pressure_listener_(
base::Bind(&RendererFrameManager::OnMemoryPressure,
base::Unretained(this))) {
// Note: With the destruction of this class the |memory_pressure_listener_|
// gets destroyed and the observer will remove itself.
max_number_of_saved_frames_ =
#if defined(OS_ANDROID)
1;
#else
std::min(5, 2 + (base::SysInfo::AmountOfPhysicalMemoryMB() / 256));
#endif
max_handles_ = base::SharedMemory::GetHandleLimit() / 8.0f;
}
RendererFrameManager::~RendererFrameManager() {}
void RendererFrameManager::CullUnlockedFrames(size_t saved_frame_limit) {
if (unlocked_frames_.size() + locked_frames_.size() > 0) {
float handles_per_frame =
HostSharedBitmapManager::current()->AllocatedBitmapCount() * 1.0f /
(unlocked_frames_.size() + locked_frames_.size());
saved_frame_limit = std::max(
1,
static_cast<int>(std::min(static_cast<float>(saved_frame_limit),
max_handles_ / handles_per_frame)));
}
while (!unlocked_frames_.empty() &&
unlocked_frames_.size() + locked_frames_.size() > saved_frame_limit) {
size_t old_size = unlocked_frames_.size();
// Should remove self from list.
unlocked_frames_.back()->EvictCurrentFrame();
DCHECK_EQ(unlocked_frames_.size() + 1, old_size);
}
}
void RendererFrameManager::OnMemoryPressure(
base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level) {
int saved_frame_limit = max_number_of_saved_frames_;
if (saved_frame_limit <= 1)
return;
int percentage = 100;
switch (memory_pressure_level) {
case base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_MODERATE:
percentage = kModeratePressurePercentage;
break;
case base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_CRITICAL:
percentage = kCriticalPressurePercentage;
break;
case base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE:
// No need to change anything when there is no pressure.
return;
}
CullUnlockedFrames(std::max(1, (saved_frame_limit * percentage) / 100));
}
} // namespace content
|
