aria2/src/SpeedCalc.cc

127 lines
3.6 KiB
C++

/* <!-- copyright */
/*
* aria2 - The high speed download utility
*
* Copyright (C) 2006 Tatsuhiro Tsujikawa
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* In addition, as a special exception, the copyright holders give
* permission to link the code of portions of this program with the
* OpenSSL library under certain conditions as described in each
* individual source file, and distribute linked combinations
* including the two.
* You must obey the GNU General Public License in all respects
* for all of the code used other than OpenSSL. If you modify
* file(s) with this exception, you may extend this exception to your
* version of the file(s), but you are not obligated to do so. If you
* do not wish to do so, delete this exception statement from your
* version. If you delete this exception statement from all source
* files in the program, then also delete it here.
*/
/* copyright --> */
#include "SpeedCalc.h"
#include <algorithm>
#include <functional>
namespace aria2 {
#define CHANGE_INTERVAL_SEC 15
class Reset {
public:
void operator()(Time& tm) {
tm.reset();
}
};
void SpeedCalc::reset() {
std::fill(&lengthArray[0], &lengthArray[2], 0);
std::for_each(&cpArray[0], &cpArray[2], Reset());
sw = 0;
maxSpeed = 0;
prevSpeed = 0;
start.reset();
accumulatedLength = 0;
nextInterval = CHANGE_INTERVAL_SEC;
}
unsigned int SpeedCalc::calculateSpeed() {
int64_t milliElapsed = cpArray[sw].differenceInMillis();
if(milliElapsed) {
unsigned int speed = lengthArray[sw]*1000/milliElapsed;
prevSpeed = speed;
maxSpeed = std::max(speed, maxSpeed);
if(isIntervalOver(milliElapsed)) {
changeSw();
}
return speed;
} else {
return prevSpeed;
}
}
unsigned int SpeedCalc::calculateSpeed(const struct timeval& now) {
int64_t milliElapsed = cpArray[sw].differenceInMillis(now);
if(milliElapsed) {
unsigned int speed = lengthArray[sw]*1000/milliElapsed;
prevSpeed = speed;
maxSpeed = std::max(speed, maxSpeed);
if(isIntervalOver(milliElapsed)) {
changeSw();
}
return speed;
} else {
return prevSpeed;
}
}
void SpeedCalc::update(size_t bytes) {
accumulatedLength += bytes;
std::transform(&lengthArray[0], &lengthArray[2], &lengthArray[0],
std::bind1st(std::plus<uint64_t>(), (uint64_t)bytes));
if(isIntervalOver()) {
changeSw();
}
}
bool SpeedCalc::isIntervalOver() const {
return nextInterval <= cpArray[sw].difference();
}
bool SpeedCalc::isIntervalOver(int64_t milliElapsed) const
{
return nextInterval <= milliElapsed/1000;
}
void SpeedCalc::changeSw() {
lengthArray[sw] = 0;
cpArray[sw].reset();
sw ^= 0x01;
nextInterval = cpArray[sw].difference()+CHANGE_INTERVAL_SEC;
}
unsigned int SpeedCalc::calculateAvgSpeed() const {
uint64_t milliElapsed = start.differenceInMillis();
if(milliElapsed) {
unsigned int speed = accumulatedLength*1000/milliElapsed;
return speed;
} else {
return 0;
}
}
} // namespace aria2