/*
* Copyright 2010 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/base/cpumonitor.h"
#include <string>
#include "webrtc/base/common.h"
#include "webrtc/base/logging.h"
#include "webrtc/base/scoped_ptr.h"
#include "webrtc/base/systeminfo.h"
#include "webrtc/base/thread.h"
#include "webrtc/base/timeutils.h"
#if defined(WEBRTC_WIN)
#include "webrtc/base/win32.h"
#include <winternl.h>
#endif
#if defined(WEBRTC_POSIX)
#include <sys/time.h>
#endif
#if defined(WEBRTC_MAC)
#include <mach/mach_host.h>
#include <mach/mach_init.h>
#include <mach/mach_port.h>
#include <mach/host_info.h>
#include <mach/task.h>
#endif // defined(WEBRTC_MAC)
#if defined(WEBRTC_LINUX)
#include <sys/resource.h>
#include <errno.h>
#include <stdio.h>
#include "webrtc/base/fileutils.h"
#include "webrtc/base/pathutils.h"
#endif // defined(WEBRTC_LINUX)
#if defined(WEBRTC_MAC)
static uint64 TimeValueTToInt64(const time_value_t &time_value) {
return rtc::kNumMicrosecsPerSec * time_value.seconds +
time_value.microseconds;
}
#endif // defined(WEBRTC_MAC)
// How CpuSampler works
// When threads switch, the time they spent is accumulated to system counters.
// The time can be treated as user, kernel or idle.
// user time is applications.
// kernel time is the OS, including the thread switching code itself.
// typically kernel time indicates IO.
// idle time is a process that wastes time when nothing is ready to run.
//
// User time is broken down by process (application). One of the applications
// is the current process. When you add up all application times, this is
// system time. If only your application is running, system time should be the
// same as process time.
//
// All cores contribute to these accumulators. A dual core process is able to
// process twice as many cycles as a single core. The actual code efficiency
// may be worse, due to contention, but the available cycles is exactly twice
// as many, and the cpu load will reflect the efficiency. Hyperthreads behave
// the same way. The load will reflect 200%, but the actual amount of work
// completed will be much less than a true dual core.
//
// Total available performance is the sum of all accumulators.
// If you tracked this for 1 second, it would essentially give you the clock
// rate - number of cycles per second.
// Speed step / Turbo Boost is not considered, so infact more processing time
// may be available.
namespace rtc {
// Note Tests on Windows show 600 ms is minimum stable interval for Windows 7.
static const int32 kDefaultInterval = 950; // Slightly under 1 second.
CpuSampler::CpuSampler()
: min_load_interval_(kDefaultInterval)
#if defined(WEBRTC_WIN)
, get_system_times_(NULL),
nt_query_system_information_(NULL),
force_fallback_(false)
#endif
{
}
CpuSampler::~CpuSampler() {
}
// Set minimum interval in ms between computing new load values. Default 950.
void CpuSampler::set_load_interval(int min_load_interval) {
min_load_interval_ = min_load_interval;
}
bool CpuSampler::Init() {
sysinfo_.reset(new SystemInfo);
cpus_ = sysinfo_->GetMaxCpus();
if (cpus_ == 0) {
return false;
}
#if defined(WEBRTC_WIN)
// Note that GetSystemTimes is available in Windows XP SP1 or later.
// http://msdn.microsoft.com/en-us/library/ms724400.aspx
// NtQuerySystemInformation is used as a fallback.
if (!force_fallback_) {
get_system_times_ = GetProcAddress(GetModuleHandle(L"kernel32.dll"),
"GetSystemTimes");
}
nt_query_system_information_ = GetProcAddress(GetModuleHandle(L"ntdll.dll"),
"NtQuerySystemInformation");
if ((get_system_times_ == NULL) && (nt_query_system_information_ == NULL)) {
return false;
}
#endif
#if defined(WEBRTC_LINUX)
Pathname sname("/proc/stat");
sfile_.reset(Filesystem::OpenFile(sname, "rb"));
if (!sfile_) {
LOG_ERR(LS_ERROR) << "open proc/stat failed:";
return false;
}
if (!sfile_->DisableBuffering()) {
LOG_ERR(LS_ERROR) << "could not disable buffering for proc/stat";
return false;
}
#endif // defined(WEBRTC_LINUX)
GetProcessLoad(); // Initialize values.
GetSystemLoad();
// Help next user call return valid data by recomputing load.
process_.prev_load_time_ = 0u;
system_.prev_load_time_ = 0u;
return true;
}
float CpuSampler::UpdateCpuLoad(uint64 current_total_times,
uint64 current_cpu_times,
uint64 *prev_total_times,
uint64 *prev_cpu_times) {
float result = 0.f;
if (current_total_times < *prev_total_times ||
current_cpu_times < *prev_cpu_times) {
LOG(LS_ERROR) << "Inconsistent time values are passed. ignored";
} else {
const uint64 cpu_diff = current_cpu_times - *prev_cpu_times;
const uint64 total_diff = current_total_times - *prev_total_times;
result = (total_diff == 0ULL ? 0.f :
static_cast<float>(1.0f * cpu_diff / total_diff));
if (result > static_cast<float>(cpus_)) {
result = static_cast<float>(cpus_);
}
*prev_total_times = current_total_times;
*prev_cpu_times = current_cpu_times;
}
return result;
}
float CpuSampler::GetSystemLoad() {
uint32 timenow = Time();
int elapsed = static_cast<int>(TimeDiff(timenow, system_.prev_load_time_));
if (min_load_interval_ != 0 && system_.prev_load_time_ != 0u &&
elapsed < min_load_interval_) {
return system_.prev_load_;
}
#if defined(WEBRTC_WIN)
uint64 total_times, cpu_times;
typedef BOOL (_stdcall *GST_PROC)(LPFILETIME, LPFILETIME, LPFILETIME);
typedef NTSTATUS (WINAPI *QSI_PROC)(SYSTEM_INFORMATION_CLASS,
PVOID, ULONG, PULONG);
GST_PROC get_system_times = reinterpret_cast<GST_PROC>(get_system_times_);
QSI_PROC nt_query_system_information = reinterpret_cast<QSI_PROC>(
nt_query_system_information_);
if (get_system_times) {
FILETIME idle_time, kernel_time, user_time;
if (!get_system_times(&idle_time, &kernel_time, &user_time)) {
LOG(LS_ERROR) << "::GetSystemTimes() failed: " << ::GetLastError();
return 0.f;
}
// kernel_time includes Kernel idle time, so no need to
// include cpu_time as total_times
total_times = ToUInt64(kernel_time) + ToUInt64(user_time);
cpu_times = total_times - ToUInt64(idle_time);
} else {
if (nt_query_system_information) {
ULONG returned_length = 0;
scoped_ptr<SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION[]> processor_info(
new SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION[cpus_]);
nt_query_system_information(
::SystemProcessorPerformanceInformation,
reinterpret_cast<void*>(processor_info.get()),
cpus_ * sizeof(SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION),
&returned_length);
if (returned_length !=
(cpus_ * sizeof(SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION))) {
LOG(LS_ERROR) << "NtQuerySystemInformation has unexpected size";
return 0.f;
}
uint64 current_idle = 0;
uint64 current_kernel = 0;
uint64 current_user = 0;
for (int ix = 0; ix < cpus_; ++ix) {
current_idle += processor_info[ix].IdleTime.QuadPart;
current_kernel += processor_info[ix].UserTime.QuadPart;
current_user += processor_info[ix].KernelTime.QuadPart;
}
total_times = current_kernel + current_user;
cpu_times = total_times - current_idle;
} else {
return 0.f;
}
}
#endif // WEBRTC_WIN
#if defined(WEBRTC_MAC)
mach_port_t mach_host = mach_host_self();
host_cpu_load_info_data_t cpu_info;
mach_msg_type_number_t info_count = HOST_CPU_LOAD_INFO_COUNT;
kern_return_t kr = host_statistics(mach_host, HOST_CPU_LOAD_INFO,
reinterpret_cast<host_info_t>(&cpu_info),
&info_count);
mach_port_deallocate(mach_task_self(), mach_host);
if (KERN_SUCCESS != kr) {
LOG(LS_ERROR) << "::host_statistics() failed";
return 0.f;
}
const uint64 cpu_times = cpu_info.cpu_ticks[CPU_STATE_NICE] +
cpu_info.cpu_ticks[CPU_STATE_SYSTEM] +
cpu_info.cpu_ticks[CPU_STATE_USER];
const uint64 total_times = cpu_times + cpu_info.cpu_ticks[CPU_STATE_IDLE];
#endif // defined(WEBRTC_MAC)
#if defined(WEBRTC_LINUX)
if (!sfile_) {
LOG(LS_ERROR) << "Invalid handle for proc/stat";
return 0.f;
}
std::string statbuf;
sfile_->SetPosition(0);
if (!sfile_->ReadLine(&statbuf)) {
LOG_ERR(LS_ERROR) << "Could not read proc/stat file";
return 0.f;
}
unsigned long long user;
unsigned long long nice;
unsigned long long system;
unsigned long long idle;
if (sscanf(statbuf.c_str(), "cpu %Lu %Lu %Lu %Lu",
&user, &nice,
&system, &idle) != 4) {
LOG_ERR(LS_ERROR) << "Could not parse cpu info";
return 0.f;
}
const uint64 cpu_times = nice + system + user;
const uint64 total_times = cpu_times + idle;
#endif // defined(WEBRTC_LINUX)
#if defined(__native_client__)
// TODO(ryanpetrie): Implement this via PPAPI when it's available.
const uint64 cpu_times = 0;
const uint64 total_times = 0;
#endif // defined(__native_client__)
system_.prev_load_time_ = timenow;
system_.prev_load_ = UpdateCpuLoad(total_times,
cpu_times * cpus_,
&system_.prev_total_times_,
&system_.prev_cpu_times_);
return system_.prev_load_;
}
float CpuSampler::GetProcessLoad() {
uint32 timenow = Time();
int elapsed = static_cast<int>(TimeDiff(timenow, process_.prev_load_time_));
if (min_load_interval_ != 0 && process_.prev_load_time_ != 0u &&
elapsed < min_load_interval_) {
return process_.prev_load_;
}
#if defined(WEBRTC_WIN)
FILETIME current_file_time;
::GetSystemTimeAsFileTime(¤t_file_time);
FILETIME create_time, exit_time, kernel_time, user_time;
if (!::GetProcessTimes(::GetCurrentProcess(),
&create_time, &exit_time, &kernel_time, &user_time)) {
LOG(LS_ERROR) << "::GetProcessTimes() failed: " << ::GetLastError();
return 0.f;
}
const uint64 total_times =
ToUInt64(current_file_time) - ToUInt64(create_time);
const uint64 cpu_times =
(ToUInt64(kernel_time) + ToUInt64(user_time));
#endif // WEBRTC_WIN
#if defined(WEBRTC_POSIX)
// Common to both OSX and Linux.
struct timeval tv;
gettimeofday(&tv, NULL);
const uint64 total_times = tv.tv_sec * kNumMicrosecsPerSec + tv.tv_usec;
#endif
#if defined(WEBRTC_MAC)
// Get live thread usage.
task_thread_times_info task_times_info;
mach_msg_type_number_t info_count = TASK_THREAD_TIMES_INFO_COUNT;
if (KERN_SUCCESS != task_info(mach_task_self(), TASK_THREAD_TIMES_INFO,
reinterpret_cast<task_info_t>(&task_times_info),
&info_count)) {
LOG(LS_ERROR) << "::task_info(TASK_THREAD_TIMES_INFO) failed";
return 0.f;
}
// Get terminated thread usage.
task_basic_info task_term_info;
info_count = TASK_BASIC_INFO_COUNT;
if (KERN_SUCCESS != task_info(mach_task_self(), TASK_BASIC_INFO,
reinterpret_cast<task_info_t>(&task_term_info),
&info_count)) {
LOG(LS_ERROR) << "::task_info(TASK_BASIC_INFO) failed";
return 0.f;
}
const uint64 cpu_times = (TimeValueTToInt64(task_times_info.user_time) +
TimeValueTToInt64(task_times_info.system_time) +
TimeValueTToInt64(task_term_info.user_time) +
TimeValueTToInt64(task_term_info.system_time));
#endif // defined(WEBRTC_MAC)
#if defined(WEBRTC_LINUX)
rusage usage;
if (getrusage(RUSAGE_SELF, &usage) < 0) {
LOG_ERR(LS_ERROR) << "getrusage failed";
return 0.f;
}
const uint64 cpu_times =
(usage.ru_utime.tv_sec + usage.ru_stime.tv_sec) * kNumMicrosecsPerSec +
usage.ru_utime.tv_usec + usage.ru_stime.tv_usec;
#endif // defined(WEBRTC_LINUX)
#if defined(__native_client__)
// TODO(ryanpetrie): Implement this via PPAPI when it's available.
const uint64 cpu_times = 0;
#endif // defined(__native_client__)
process_.prev_load_time_ = timenow;
process_.prev_load_ = UpdateCpuLoad(total_times,
cpu_times,
&process_.prev_total_times_,
&process_.prev_cpu_times_);
return process_.prev_load_;
}
int CpuSampler::GetMaxCpus() const {
return cpus_;
}
int CpuSampler::GetCurrentCpus() {
return sysinfo_->GetCurCpus();
}
///////////////////////////////////////////////////////////////////
// Implementation of class CpuMonitor.
CpuMonitor::CpuMonitor(Thread* thread)
: monitor_thread_(thread) {
}
CpuMonitor::~CpuMonitor() {
Stop();
}
void CpuMonitor::set_thread(Thread* thread) {
ASSERT(monitor_thread_ == NULL || monitor_thread_ == thread);
monitor_thread_ = thread;
}
bool CpuMonitor::Start(int period_ms) {
if (!monitor_thread_ || !sampler_.Init()) return false;
monitor_thread_->SignalQueueDestroyed.connect(
this, &CpuMonitor::OnMessageQueueDestroyed);
period_ms_ = period_ms;
monitor_thread_->PostDelayed(period_ms_, this);
return true;
}
void CpuMonitor::Stop() {
if (monitor_thread_) {
monitor_thread_->Clear(this);
}
}
void CpuMonitor::OnMessage(Message* msg) {
int max_cpus = sampler_.GetMaxCpus();
int current_cpus = sampler_.GetCurrentCpus();
float process_load = sampler_.GetProcessLoad();
float system_load = sampler_.GetSystemLoad();
SignalUpdate(current_cpus, max_cpus, process_load, system_load);
if (monitor_thread_) {
monitor_thread_->PostDelayed(period_ms_, this);
}
}
} // namespace rtc