| // Copyright 2018 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/startup_helper.h" |
| |
| #include <algorithm> |
| #include <memory> |
| #include <set> |
| #include <string> |
| |
| #include "base/base_switches.h" |
| #include "base/command_line.h" |
| #include "base/metrics/field_trial_params.h" |
| #include "base/system/sys_info.h" |
| #include "base/task/thread_pool/initialization_util.h" |
| #include "base/task/thread_pool/thread_pool_instance.h" |
| #include "build/build_config.h" |
| #include "content/common/thread_pool_util.h" |
| #include "content/public/common/content_switch_dependent_feature_overrides.h" |
| #include "content/public/common/content_switches.h" |
| |
| namespace content { |
| |
| std::unique_ptr<base::FieldTrialList> SetUpFieldTrialsAndFeatureList() { |
| std::unique_ptr<base::FieldTrialList> field_trial_list; |
| if (!base::FieldTrialList::GetInstance()) |
| field_trial_list = std::make_unique<base::FieldTrialList>(nullptr); |
| const base::CommandLine* command_line = |
| base::CommandLine::ForCurrentProcess(); |
| |
| // Ensure any field trials specified on the command line are initialized. |
| if (command_line->HasSwitch(::switches::kForceFieldTrials)) { |
| // Create field trials without activating them, so that this behaves in a |
| // consistent manner with field trials created from the server. |
| bool result = base::FieldTrialList::CreateTrialsFromString( |
| command_line->GetSwitchValueASCII(::switches::kForceFieldTrials)); |
| CHECK(result) << "Invalid --" << ::switches::kForceFieldTrials |
| << " list specified."; |
| } |
| |
| base::FeatureList::InitializeInstance( |
| command_line->GetSwitchValueASCII(switches::kEnableFeatures), |
| command_line->GetSwitchValueASCII(switches::kDisableFeatures), |
| GetSwitchDependentFeatureOverrides(*command_line)); |
| return field_trial_list; |
| } |
| |
| namespace { |
| #if defined(OS_ANDROID) |
| // Mobile config, for iOS see ios/web/app/web_main_loop.cc. |
| constexpr int kThreadPoolDefaultMin = 6; |
| constexpr int kThreadPoolMax = 8; |
| constexpr double kThreadPoolCoresMultiplier = 0.6; |
| constexpr int kThreadPoolOffset = 0; |
| #else |
| // Desktop config. |
| constexpr int kThreadPoolDefaultMin = 16; |
| constexpr int kThreadPoolMax = 32; |
| constexpr double kThreadPoolCoresMultiplier = 0.6; |
| constexpr int kThreadPoolOffset = 0; |
| #endif |
| |
| const base::Feature kBrowserThreadPoolAdjustment{ |
| "BrowserThreadPoolAdjustment", base::FEATURE_DISABLED_BY_DEFAULT}; |
| |
| const base::FeatureParam<int> kBrowserThreadPoolMin{ |
| &kBrowserThreadPoolAdjustment, "min", kThreadPoolDefaultMin}; |
| } // namespace |
| |
| // TODO(scheduler-dev): Standardize thread pool logic and remove the need for |
| // specifying thread count manually. |
| void StartBrowserThreadPool() { |
| // Ensure we always support at least one thread regardless of the field trial |
| // param setting. |
| int min = std::max(kBrowserThreadPoolMin.Get(), 1); |
| base::ThreadPoolInstance::InitParams thread_pool_init_params = { |
| base::RecommendedMaxNumberOfThreadsInThreadGroup( |
| min, kThreadPoolMax, kThreadPoolCoresMultiplier, kThreadPoolOffset)}; |
| |
| #if defined(OS_WIN) |
| thread_pool_init_params.common_thread_pool_environment = base:: |
| ThreadPoolInstance::InitParams::CommonThreadPoolEnvironment::COM_MTA; |
| #endif |
| |
| // If a renderer lives in the browser process, adjust the number of |
| // threads in the foreground pool. |
| if (base::CommandLine::ForCurrentProcess()->HasSwitch( |
| switches::kSingleProcess)) { |
| thread_pool_init_params.max_num_foreground_threads = |
| std::max(GetMinForegroundThreadsInRendererThreadPool(), |
| thread_pool_init_params.max_num_foreground_threads); |
| } |
| |
| base::ThreadPoolInstance::Get()->Start(thread_pool_init_params); |
| } |
| |
| } // namespace content |