1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/lemon/time_measure.h Sun Mar 30 22:16:35 2008 +0100
1.3 @@ -0,0 +1,541 @@
1.4 +/* -*- C++ -*-
1.5 + *
1.6 + * This file is a part of LEMON, a generic C++ optimization library
1.7 + *
1.8 + * Copyright (C) 2003-2008
1.9 + * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
1.10 + * (Egervary Research Group on Combinatorial Optimization, EGRES).
1.11 + *
1.12 + * Permission to use, modify and distribute this software is granted
1.13 + * provided that this copyright notice appears in all copies. For
1.14 + * precise terms see the accompanying LICENSE file.
1.15 + *
1.16 + * This software is provided "AS IS" with no warranty of any kind,
1.17 + * express or implied, and with no claim as to its suitability for any
1.18 + * purpose.
1.19 + *
1.20 + */
1.21 +
1.22 +#ifndef LEMON_TIME_MEASURE_H
1.23 +#define LEMON_TIME_MEASURE_H
1.24 +
1.25 +///\ingroup timecount
1.26 +///\file
1.27 +///\brief Tools for measuring cpu usage
1.28 +
1.29 +#include <sys/times.h>
1.30 +
1.31 +#include <sys/time.h>
1.32 +#include <fstream>
1.33 +#include <iostream>
1.34 +#include <unistd.h>
1.35 +
1.36 +namespace lemon {
1.37 +
1.38 + /// \addtogroup timecount
1.39 + /// @{
1.40 +
1.41 + /// A class to store (cpu)time instances.
1.42 +
1.43 + /// This class stores five time values.
1.44 + /// - a real time
1.45 + /// - a user cpu time
1.46 + /// - a system cpu time
1.47 + /// - a user cpu time of children
1.48 + /// - a system cpu time of children
1.49 + ///
1.50 + /// TimeStamp's can be added to or substracted from each other and
1.51 + /// they can be pushed to a stream.
1.52 + ///
1.53 + /// In most cases, perhaps the \ref Timer or the \ref TimeReport
1.54 + /// class is what you want to use instead.
1.55 + ///
1.56 + ///\author Alpar Juttner
1.57 +
1.58 + class TimeStamp
1.59 + {
1.60 + struct rtms
1.61 + {
1.62 + double tms_utime;
1.63 + double tms_stime;
1.64 + double tms_cutime;
1.65 + double tms_cstime;
1.66 + rtms() {}
1.67 + rtms(tms ts) : tms_utime(ts.tms_utime), tms_stime(ts.tms_stime),
1.68 + tms_cutime(ts.tms_cutime), tms_cstime(ts.tms_cstime) {}
1.69 + };
1.70 + rtms ts;
1.71 + double real_time;
1.72 +
1.73 + rtms &getTms() {return ts;}
1.74 + const rtms &getTms() const {return ts;}
1.75 +
1.76 + void _reset() {
1.77 + ts.tms_utime = ts.tms_stime = ts.tms_cutime = ts.tms_cstime = 0;
1.78 + real_time = 0;
1.79 + }
1.80 +
1.81 + public:
1.82 +
1.83 + ///Read the current time values of the process
1.84 + void stamp()
1.85 + {
1.86 + timeval tv;
1.87 + tms _ts;
1.88 + times(&_ts);
1.89 + gettimeofday(&tv, 0);real_time=tv.tv_sec+double(tv.tv_usec)/1e6;
1.90 + ts=_ts;
1.91 + }
1.92 +
1.93 + /// Constructor initializing with zero
1.94 + TimeStamp()
1.95 + { _reset(); }
1.96 + ///Constructor initializing with the current time values of the process
1.97 + TimeStamp(void *) { stamp();}
1.98 +
1.99 + ///Set every time value to zero
1.100 + TimeStamp &reset() {_reset();return *this;}
1.101 +
1.102 + ///\e
1.103 + TimeStamp &operator+=(const TimeStamp &b)
1.104 + {
1.105 + ts.tms_utime+=b.ts.tms_utime;
1.106 + ts.tms_stime+=b.ts.tms_stime;
1.107 + ts.tms_cutime+=b.ts.tms_cutime;
1.108 + ts.tms_cstime+=b.ts.tms_cstime;
1.109 + real_time+=b.real_time;
1.110 + return *this;
1.111 + }
1.112 + ///\e
1.113 + TimeStamp operator+(const TimeStamp &b) const
1.114 + {
1.115 + TimeStamp t(*this);
1.116 + return t+=b;
1.117 + }
1.118 + ///\e
1.119 + TimeStamp &operator-=(const TimeStamp &b)
1.120 + {
1.121 + ts.tms_utime-=b.ts.tms_utime;
1.122 + ts.tms_stime-=b.ts.tms_stime;
1.123 + ts.tms_cutime-=b.ts.tms_cutime;
1.124 + ts.tms_cstime-=b.ts.tms_cstime;
1.125 + real_time-=b.real_time;
1.126 + return *this;
1.127 + }
1.128 + ///\e
1.129 + TimeStamp operator-(const TimeStamp &b) const
1.130 + {
1.131 + TimeStamp t(*this);
1.132 + return t-=b;
1.133 + }
1.134 + ///\e
1.135 + TimeStamp &operator*=(double b)
1.136 + {
1.137 + ts.tms_utime*=b;
1.138 + ts.tms_stime*=b;
1.139 + ts.tms_cutime*=b;
1.140 + ts.tms_cstime*=b;
1.141 + real_time*=b;
1.142 + return *this;
1.143 + }
1.144 + ///\e
1.145 + TimeStamp operator*(double b) const
1.146 + {
1.147 + TimeStamp t(*this);
1.148 + return t*=b;
1.149 + }
1.150 + friend TimeStamp operator*(double b,const TimeStamp &t);
1.151 + ///\e
1.152 + TimeStamp &operator/=(double b)
1.153 + {
1.154 + ts.tms_utime/=b;
1.155 + ts.tms_stime/=b;
1.156 + ts.tms_cutime/=b;
1.157 + ts.tms_cstime/=b;
1.158 + real_time/=b;
1.159 + return *this;
1.160 + }
1.161 + ///\e
1.162 + TimeStamp operator/(double b) const
1.163 + {
1.164 + TimeStamp t(*this);
1.165 + return t/=b;
1.166 + }
1.167 + ///The time ellapsed since the last call of stamp()
1.168 + TimeStamp ellapsed() const
1.169 + {
1.170 + TimeStamp t(NULL);
1.171 + return t-*this;
1.172 + }
1.173 +
1.174 + friend std::ostream& operator<<(std::ostream& os,const TimeStamp &t);
1.175 +
1.176 + ///Gives back the user time of the process
1.177 + double userTime() const
1.178 + {
1.179 + return double(ts.tms_utime)/sysconf(_SC_CLK_TCK);
1.180 + }
1.181 + ///Gives back the system time of the process
1.182 + double systemTime() const
1.183 + {
1.184 + return double(ts.tms_stime)/sysconf(_SC_CLK_TCK);
1.185 + }
1.186 + ///Gives back the user time of the process' children
1.187 + double cUserTime() const
1.188 + {
1.189 + return double(ts.tms_cutime)/sysconf(_SC_CLK_TCK);
1.190 + }
1.191 + ///Gives back the user time of the process' children
1.192 + double cSystemTime() const
1.193 + {
1.194 + return double(ts.tms_cstime)/sysconf(_SC_CLK_TCK);
1.195 + }
1.196 + ///Gives back the real time
1.197 + double realTime() const {return real_time;}
1.198 + };
1.199 +
1.200 + TimeStamp operator*(double b,const TimeStamp &t)
1.201 + {
1.202 + return t*b;
1.203 + }
1.204 +
1.205 + ///Prints the time counters
1.206 +
1.207 + ///Prints the time counters in the following form:
1.208 + ///
1.209 + /// <tt>u: XX.XXs s: XX.XXs cu: XX.XXs cs: XX.XXs real: XX.XXs</tt>
1.210 + ///
1.211 + /// where the values are the
1.212 + /// \li \c u: user cpu time,
1.213 + /// \li \c s: system cpu time,
1.214 + /// \li \c cu: user cpu time of children,
1.215 + /// \li \c cs: system cpu time of children,
1.216 + /// \li \c real: real time.
1.217 + /// \relates TimeStamp
1.218 + inline std::ostream& operator<<(std::ostream& os,const TimeStamp &t)
1.219 + {
1.220 + long cls = sysconf(_SC_CLK_TCK);
1.221 + os << "u: " << double(t.getTms().tms_utime)/cls <<
1.222 + "s, s: " << double(t.getTms().tms_stime)/cls <<
1.223 + "s, cu: " << double(t.getTms().tms_cutime)/cls <<
1.224 + "s, cs: " << double(t.getTms().tms_cstime)/cls <<
1.225 + "s, real: " << t.realTime() << "s";
1.226 + return os;
1.227 + }
1.228 +
1.229 + ///Class for measuring the cpu time and real time usage of the process
1.230 +
1.231 + ///Class for measuring the cpu time and real time usage of the process.
1.232 + ///It is quite easy-to-use, here is a short example.
1.233 + ///\code
1.234 + /// #include<lemon/time_measure.h>
1.235 + /// #include<iostream>
1.236 + ///
1.237 + /// int main()
1.238 + /// {
1.239 + ///
1.240 + /// ...
1.241 + ///
1.242 + /// Timer t;
1.243 + /// doSomething();
1.244 + /// std::cout << t << '\n';
1.245 + /// t.restart();
1.246 + /// doSomethingElse();
1.247 + /// std::cout << t << '\n';
1.248 + ///
1.249 + /// ...
1.250 + ///
1.251 + /// }
1.252 + ///\endcode
1.253 + ///
1.254 + ///The \ref Timer can also be \ref stop() "stopped" and
1.255 + ///\ref start() "started" again, so it is possible to compute collected
1.256 + ///running times.
1.257 + ///
1.258 + ///\warning Depending on the operation system and its actual configuration
1.259 + ///the time counters have a certain (10ms on a typical Linux system)
1.260 + ///granularity.
1.261 + ///Therefore this tool is not appropriate to measure very short times.
1.262 + ///Also, if you start and stop the timer very frequently, it could lead to
1.263 + ///distorted results.
1.264 + ///
1.265 + ///\note If you want to measure the running time of the execution of a certain
1.266 + ///function, consider the usage of \ref TimeReport instead.
1.267 + ///
1.268 + ///\todo This shouldn't be Unix (Linux) specific.
1.269 + ///\sa TimeReport
1.270 + ///
1.271 + ///\author Alpar Juttner
1.272 + class Timer
1.273 + {
1.274 + int _running; //Timer is running iff _running>0; (_running>=0 always holds)
1.275 + TimeStamp start_time; //This is the relativ start-time if the timer
1.276 + //is _running, the collected _running time otherwise.
1.277 +
1.278 + void _reset() {if(_running) start_time.stamp(); else start_time.reset();}
1.279 +
1.280 + public:
1.281 + ///Constructor.
1.282 +
1.283 + ///\param run indicates whether or not the timer starts immediately.
1.284 + ///
1.285 + Timer(bool run=true) :_running(run) {_reset();}
1.286 +
1.287 + ///\name Control the state of the timer
1.288 + ///Basically a Timer can be either running or stopped,
1.289 + ///but it provides a bit finer control on the execution.
1.290 + ///The \ref Timer also counts the number of \ref start()
1.291 + ///executions, and is stops only after the same amount (or more)
1.292 + ///\ref stop() "stop()"s. This can be useful e.g. to compute the running time
1.293 + ///of recursive functions.
1.294 + ///
1.295 +
1.296 + ///@{
1.297 +
1.298 + ///Reset and stop the time counters
1.299 +
1.300 + ///This function resets and stops the time counters
1.301 + ///\sa restart()
1.302 + void reset()
1.303 + {
1.304 + _running=0;
1.305 + _reset();
1.306 + }
1.307 +
1.308 + ///Start the time counters
1.309 +
1.310 + ///This function starts the time counters.
1.311 + ///
1.312 + ///If the timer is started more than ones, it will remain running
1.313 + ///until the same amount of \ref stop() is called.
1.314 + ///\sa stop()
1.315 + void start()
1.316 + {
1.317 + if(_running) _running++;
1.318 + else {
1.319 + _running=1;
1.320 + TimeStamp t;
1.321 + t.stamp();
1.322 + start_time=t-start_time;
1.323 + }
1.324 + }
1.325 +
1.326 +
1.327 + ///Stop the time counters
1.328 +
1.329 + ///This function stops the time counters. If start() was executed more than
1.330 + ///once, then the same number of stop() execution is necessary the really
1.331 + ///stop the timer.
1.332 + ///
1.333 + ///\sa halt()
1.334 + ///\sa start()
1.335 + ///\sa restart()
1.336 + ///\sa reset()
1.337 +
1.338 + void stop()
1.339 + {
1.340 + if(_running && !--_running) {
1.341 + TimeStamp t;
1.342 + t.stamp();
1.343 + start_time=t-start_time;
1.344 + }
1.345 + }
1.346 +
1.347 + ///Halt (i.e stop immediately) the time counters
1.348 +
1.349 + ///This function stops immediately the time counters, i.e. <tt>t.stop()</tt>
1.350 + ///is a faster
1.351 + ///equivalent of the following.
1.352 + ///\code
1.353 + /// while(t.running()) t.stop()
1.354 + ///\endcode
1.355 + ///
1.356 + ///
1.357 + ///\sa stop()
1.358 + ///\sa restart()
1.359 + ///\sa reset()
1.360 +
1.361 + void halt()
1.362 + {
1.363 + if(_running) {
1.364 + _running=0;
1.365 + TimeStamp t;
1.366 + t.stamp();
1.367 + start_time=t-start_time;
1.368 + }
1.369 + }
1.370 +
1.371 + ///Returns the running state of the timer
1.372 +
1.373 + ///This function returns the number of stop() exections that is
1.374 + ///necessary to really stop the timer.
1.375 + ///For example the timer
1.376 + ///is running if and only if the return value is \c true
1.377 + ///(i.e. greater than
1.378 + ///zero).
1.379 + int running() { return _running; }
1.380 +
1.381 +
1.382 + ///Restart the time counters
1.383 +
1.384 + ///This function is a shorthand for
1.385 + ///a reset() and a start() calls.
1.386 + ///
1.387 + void restart()
1.388 + {
1.389 + reset();
1.390 + start();
1.391 + }
1.392 +
1.393 + ///@}
1.394 +
1.395 + ///\name Query Functions for the ellapsed time
1.396 +
1.397 + ///@{
1.398 +
1.399 + ///Gives back the ellapsed user time of the process
1.400 + double userTime() const
1.401 + {
1.402 + return operator TimeStamp().userTime();
1.403 + }
1.404 + ///Gives back the ellapsed system time of the process
1.405 + double systemTime() const
1.406 + {
1.407 + return operator TimeStamp().systemTime();
1.408 + }
1.409 + ///Gives back the ellapsed user time of the process' children
1.410 + double cUserTime() const
1.411 + {
1.412 + return operator TimeStamp().cUserTime();
1.413 + }
1.414 + ///Gives back the ellapsed user time of the process' children
1.415 + double cSystemTime() const
1.416 + {
1.417 + return operator TimeStamp().cSystemTime();
1.418 + }
1.419 + ///Gives back the ellapsed real time
1.420 + double realTime() const
1.421 + {
1.422 + return operator TimeStamp().realTime();
1.423 + }
1.424 + ///Computes the ellapsed time
1.425 +
1.426 + ///This conversion computes the ellapsed time, therefore you can print
1.427 + ///the ellapsed time like this.
1.428 + ///\code
1.429 + /// Timer t;
1.430 + /// doSomething();
1.431 + /// std::cout << t << '\n';
1.432 + ///\endcode
1.433 + operator TimeStamp () const
1.434 + {
1.435 + TimeStamp t;
1.436 + t.stamp();
1.437 + return _running?t-start_time:start_time;
1.438 + }
1.439 +
1.440 +
1.441 + ///@}
1.442 + };
1.443 +
1.444 + ///Same as \ref Timer but prints a report on destruction.
1.445 +
1.446 + ///Same as \ref Timer but prints a report on destruction.
1.447 + ///This example shows its usage.
1.448 + ///\code
1.449 + /// void myAlg(ListGraph &g,int n)
1.450 + /// {
1.451 + /// TimeReport tr("Running time of myAlg: ");
1.452 + /// ... //Here comes the algorithm
1.453 + /// }
1.454 + ///\endcode
1.455 + ///
1.456 + ///\sa Timer
1.457 + ///\sa NoTimeReport
1.458 + ///\todo There is no test case for this
1.459 + class TimeReport : public Timer
1.460 + {
1.461 + std::string _title;
1.462 + std::ostream &_os;
1.463 + public:
1.464 + ///\e
1.465 +
1.466 + ///\param title This text will be printed before the ellapsed time.
1.467 + ///\param os The stream to print the report to.
1.468 + ///\param run Sets whether the timer should start immediately.
1.469 +
1.470 + TimeReport(std::string title,std::ostream &os=std::cerr,bool run=true)
1.471 + : Timer(run), _title(title), _os(os){}
1.472 + ///\e Prints the ellapsed time on destruction.
1.473 + ~TimeReport()
1.474 + {
1.475 + _os << _title << *this << std::endl;
1.476 + }
1.477 + };
1.478 +
1.479 + ///'Do nothing' version of \ref TimeReport
1.480 +
1.481 + ///\sa TimeReport
1.482 + ///
1.483 + class NoTimeReport
1.484 + {
1.485 + public:
1.486 + ///\e
1.487 + NoTimeReport(std::string,std::ostream &,bool) {}
1.488 + ///\e
1.489 + NoTimeReport(std::string,std::ostream &) {}
1.490 + ///\e
1.491 + NoTimeReport(std::string) {}
1.492 + ///\e Do nothing.
1.493 + ~NoTimeReport() {}
1.494 +
1.495 + operator TimeStamp () const { return TimeStamp(); }
1.496 + void reset() {}
1.497 + void start() {}
1.498 + void stop() {}
1.499 + void halt() {}
1.500 + int running() { return 0; }
1.501 + void restart() {}
1.502 + double userTime() const { return 0; }
1.503 + double systemTime() const { return 0; }
1.504 + double cUserTime() const { return 0; }
1.505 + double cSystemTime() const { return 0; }
1.506 + double realTime() const { return 0; }
1.507 + };
1.508 +
1.509 + ///Tool to measure the running time more exactly.
1.510 +
1.511 + ///This function calls \c f several times and returns the average
1.512 + ///running time. The number of the executions will be choosen in such a way
1.513 + ///that the full real running time will be roughly between \c min_time
1.514 + ///and <tt>2*min_time</tt>.
1.515 + ///\param f the function object to be measured.
1.516 + ///\param min_time the minimum total running time.
1.517 + ///\retval num if it is not \c NULL, then the actual
1.518 + /// number of execution of \c f will be written into <tt>*num</tt>.
1.519 + ///\retval full_time if it is not \c NULL, then the actual
1.520 + /// total running time will be written into <tt>*full_time</tt>.
1.521 + ///\return The average running time of \c f.
1.522 +
1.523 + template<class F>
1.524 + TimeStamp runningTimeTest(F f,double min_time=10,unsigned int *num = NULL,
1.525 + TimeStamp *full_time=NULL)
1.526 + {
1.527 + TimeStamp full;
1.528 + unsigned int total=0;
1.529 + Timer t;
1.530 + for(unsigned int tn=1;tn <= 1U<<31 && full.realTime()<=min_time; tn*=2) {
1.531 + for(;total<tn;total++) f();
1.532 + full=t;
1.533 + }
1.534 + if(num) *num=total;
1.535 + if(full_time) *full_time=full;
1.536 + return full/total;
1.537 + }
1.538 +
1.539 + /// @}
1.540 +
1.541 +
1.542 +} //namespace lemon
1.543 +
1.544 +#endif //LEMON_TIME_MEASURE_H