blob: f772037b0df54ab4e9c365ba9a388016533f6b3c [file] [log] [blame]
/*
* Copyright (c) 2012 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/video/call_stats.h"
#include <algorithm>
#include "webrtc/base/checks.h"
#include "webrtc/base/constructormagic.h"
#include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h"
#include "webrtc/system_wrappers/include/metrics.h"
namespace webrtc {
namespace {
// Time interval for updating the observers.
const int64_t kUpdateIntervalMs = 1000;
// Weight factor to apply to the average rtt.
const float kWeightFactor = 0.3f;
void RemoveOldReports(int64_t now, std::list<CallStats::RttTime>* reports) {
// A rtt report is considered valid for this long.
const int64_t kRttTimeoutMs = 1500;
while (!reports->empty() &&
(now - reports->front().time) > kRttTimeoutMs) {
reports->pop_front();
}
}
int64_t GetMaxRttMs(std::list<CallStats::RttTime>* reports) {
if (reports->empty())
return -1;
int64_t max_rtt_ms = 0;
for (const CallStats::RttTime& rtt_time : *reports)
max_rtt_ms = std::max(rtt_time.rtt, max_rtt_ms);
return max_rtt_ms;
}
int64_t GetAvgRttMs(std::list<CallStats::RttTime>* reports) {
if (reports->empty()) {
return -1;
}
int64_t sum = 0;
for (std::list<CallStats::RttTime>::const_iterator it = reports->begin();
it != reports->end(); ++it) {
sum += it->rtt;
}
return sum / reports->size();
}
void UpdateAvgRttMs(std::list<CallStats::RttTime>* reports, int64_t* avg_rtt) {
int64_t cur_rtt_ms = GetAvgRttMs(reports);
if (cur_rtt_ms == -1) {
// Reset.
*avg_rtt = -1;
return;
}
if (*avg_rtt == -1) {
// Initialize.
*avg_rtt = cur_rtt_ms;
return;
}
*avg_rtt = *avg_rtt * (1.0f - kWeightFactor) + cur_rtt_ms * kWeightFactor;
}
} // namespace
class RtcpObserver : public RtcpRttStats {
public:
explicit RtcpObserver(CallStats* owner) : owner_(owner) {}
virtual ~RtcpObserver() {}
virtual void OnRttUpdate(int64_t rtt) {
owner_->OnRttUpdate(rtt);
}
// Returns the average RTT.
virtual int64_t LastProcessedRtt() const {
return owner_->avg_rtt_ms();
}
private:
CallStats* owner_;
RTC_DISALLOW_COPY_AND_ASSIGN(RtcpObserver);
};
CallStats::CallStats(Clock* clock)
: clock_(clock),
rtcp_rtt_stats_(new RtcpObserver(this)),
last_process_time_(clock_->TimeInMilliseconds()),
max_rtt_ms_(-1),
avg_rtt_ms_(-1),
sum_avg_rtt_ms_(0),
num_avg_rtt_(0),
time_of_first_rtt_ms_(-1) {}
CallStats::~CallStats() {
RTC_DCHECK(observers_.empty());
UpdateHistograms();
}
int64_t CallStats::TimeUntilNextProcess() {
return last_process_time_ + kUpdateIntervalMs - clock_->TimeInMilliseconds();
}
void CallStats::Process() {
rtc::CritScope cs(&crit_);
int64_t now = clock_->TimeInMilliseconds();
if (now < last_process_time_ + kUpdateIntervalMs)
return;
last_process_time_ = now;
RemoveOldReports(now, &reports_);
max_rtt_ms_ = GetMaxRttMs(&reports_);
UpdateAvgRttMs(&reports_, &avg_rtt_ms_);
// If there is a valid rtt, update all observers with the max rtt.
if (max_rtt_ms_ >= 0) {
RTC_DCHECK_GE(avg_rtt_ms_, 0);
for (std::list<CallStatsObserver*>::iterator it = observers_.begin();
it != observers_.end(); ++it) {
(*it)->OnRttUpdate(avg_rtt_ms_, max_rtt_ms_);
}
// Sum for Histogram of average RTT reported over the entire call.
sum_avg_rtt_ms_ += avg_rtt_ms_;
++num_avg_rtt_;
}
}
int64_t CallStats::avg_rtt_ms() const {
rtc::CritScope cs(&crit_);
return avg_rtt_ms_;
}
RtcpRttStats* CallStats::rtcp_rtt_stats() const {
return rtcp_rtt_stats_.get();
}
void CallStats::RegisterStatsObserver(CallStatsObserver* observer) {
rtc::CritScope cs(&crit_);
for (std::list<CallStatsObserver*>::iterator it = observers_.begin();
it != observers_.end(); ++it) {
if (*it == observer)
return;
}
observers_.push_back(observer);
}
void CallStats::DeregisterStatsObserver(CallStatsObserver* observer) {
rtc::CritScope cs(&crit_);
for (std::list<CallStatsObserver*>::iterator it = observers_.begin();
it != observers_.end(); ++it) {
if (*it == observer) {
observers_.erase(it);
return;
}
}
}
void CallStats::OnRttUpdate(int64_t rtt) {
rtc::CritScope cs(&crit_);
int64_t now_ms = clock_->TimeInMilliseconds();
reports_.push_back(RttTime(rtt, now_ms));
if (time_of_first_rtt_ms_ == -1)
time_of_first_rtt_ms_ = now_ms;
}
void CallStats::UpdateHistograms() {
rtc::CritScope cs(&crit_);
if (time_of_first_rtt_ms_ == -1 || num_avg_rtt_ < 1)
return;
int64_t elapsed_sec =
(clock_->TimeInMilliseconds() - time_of_first_rtt_ms_) / 1000;
if (elapsed_sec >= metrics::kMinRunTimeInSeconds) {
int64_t avg_rtt_ms = (sum_avg_rtt_ms_ + num_avg_rtt_ / 2) / num_avg_rtt_;
RTC_HISTOGRAM_COUNTS_10000(
"WebRTC.Video.AverageRoundTripTimeInMilliseconds", avg_rtt_ms);
}
}
} // namespace webrtc