COIN-OR::LEMON - Graph Library

source: lemon-1.2/lemon/time_measure.h @ 481:daddd623ac9a

Last change on this file since 481:daddd623ac9a was 481:daddd623ac9a, checked in by Alpar Juttner <alpar@…>, 11 years ago

Set the compatibily related MSVC defines only if they has't been defined yet

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1/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 *
3 * This file is a part of LEMON, a generic C++ optimization library.
4 *
5 * Copyright (C) 2003-2008
6 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 *
9 * Permission to use, modify and distribute this software is granted
10 * provided that this copyright notice appears in all copies. For
11 * precise terms see the accompanying LICENSE file.
12 *
13 * This software is provided "AS IS" with no warranty of any kind,
14 * express or implied, and with no claim as to its suitability for any
15 * purpose.
16 *
17 */
18
19#ifndef LEMON_TIME_MEASURE_H
20#define LEMON_TIME_MEASURE_H
21
22///\ingroup timecount
23///\file
24///\brief Tools for measuring cpu usage
25
26#ifdef WIN32
27#ifndef WIN32_LEAN_AND_MEAN
28#define WIN32_LEAN_AND_MEAN
29#endif
30#ifndef NOMINMAX
31#define NOMINMAX
32#endif
33#include <windows.h>
34#include <cmath>
35#else
36#include <unistd.h>
37#include <sys/times.h>
38#include <sys/time.h>
39#endif
40
41#include <string>
42#include <fstream>
43#include <iostream>
44
45namespace lemon {
46
47  /// \addtogroup timecount
48  /// @{
49
50  /// A class to store (cpu)time instances.
51
52  /// This class stores five time values.
53  /// - a real time
54  /// - a user cpu time
55  /// - a system cpu time
56  /// - a user cpu time of children
57  /// - a system cpu time of children
58  ///
59  /// TimeStamp's can be added to or substracted from each other and
60  /// they can be pushed to a stream.
61  ///
62  /// In most cases, perhaps the \ref Timer or the \ref TimeReport
63  /// class is what you want to use instead.
64
65  class TimeStamp
66  {
67    double utime;
68    double stime;
69    double cutime;
70    double cstime;
71    double rtime;
72
73    void _reset() {
74      utime = stime = cutime = cstime = rtime = 0;
75    }
76
77  public:
78
79    ///Read the current time values of the process
80    void stamp()
81    {
82#ifndef WIN32
83      timeval tv;
84      gettimeofday(&tv, 0);
85      rtime=tv.tv_sec+double(tv.tv_usec)/1e6;
86
87      tms ts;
88      double tck=sysconf(_SC_CLK_TCK);
89      times(&ts);
90      utime=ts.tms_utime/tck;
91      stime=ts.tms_stime/tck;
92      cutime=ts.tms_cutime/tck;
93      cstime=ts.tms_cstime/tck;
94#else
95      static const double ch = 4294967296.0e-7;
96      static const double cl = 1.0e-7;
97
98      FILETIME system;
99      GetSystemTimeAsFileTime(&system);
100      rtime = ch * system.dwHighDateTime + cl * system.dwLowDateTime;
101
102      FILETIME create, exit, kernel, user;
103      if (GetProcessTimes(GetCurrentProcess(),&create, &exit, &kernel, &user)) {
104        utime = ch * user.dwHighDateTime + cl * user.dwLowDateTime;
105        stime = ch * kernel.dwHighDateTime + cl * kernel.dwLowDateTime;
106        cutime = 0;
107        cstime = 0;
108      } else {
109        rtime = 0;
110        utime = 0;
111        stime = 0;
112        cutime = 0;
113        cstime = 0;
114      }
115#endif
116    }
117
118    /// Constructor initializing with zero
119    TimeStamp()
120    { _reset(); }
121    ///Constructor initializing with the current time values of the process
122    TimeStamp(void *) { stamp();}
123
124    ///Set every time value to zero
125    TimeStamp &reset() {_reset();return *this;}
126
127    ///\e
128    TimeStamp &operator+=(const TimeStamp &b)
129    {
130      utime+=b.utime;
131      stime+=b.stime;
132      cutime+=b.cutime;
133      cstime+=b.cstime;
134      rtime+=b.rtime;
135      return *this;
136    }
137    ///\e
138    TimeStamp operator+(const TimeStamp &b) const
139    {
140      TimeStamp t(*this);
141      return t+=b;
142    }
143    ///\e
144    TimeStamp &operator-=(const TimeStamp &b)
145    {
146      utime-=b.utime;
147      stime-=b.stime;
148      cutime-=b.cutime;
149      cstime-=b.cstime;
150      rtime-=b.rtime;
151      return *this;
152    }
153    ///\e
154    TimeStamp operator-(const TimeStamp &b) const
155    {
156      TimeStamp t(*this);
157      return t-=b;
158    }
159    ///\e
160    TimeStamp &operator*=(double b)
161    {
162      utime*=b;
163      stime*=b;
164      cutime*=b;
165      cstime*=b;
166      rtime*=b;
167      return *this;
168    }
169    ///\e
170    TimeStamp operator*(double b) const
171    {
172      TimeStamp t(*this);
173      return t*=b;
174    }
175    friend TimeStamp operator*(double b,const TimeStamp &t);
176    ///\e
177    TimeStamp &operator/=(double b)
178    {
179      utime/=b;
180      stime/=b;
181      cutime/=b;
182      cstime/=b;
183      rtime/=b;
184      return *this;
185    }
186    ///\e
187    TimeStamp operator/(double b) const
188    {
189      TimeStamp t(*this);
190      return t/=b;
191    }
192    ///The time ellapsed since the last call of stamp()
193    TimeStamp ellapsed() const
194    {
195      TimeStamp t(NULL);
196      return t-*this;
197    }
198
199    friend std::ostream& operator<<(std::ostream& os,const TimeStamp &t);
200
201    ///Gives back the user time of the process
202    double userTime() const
203    {
204      return utime;
205    }
206    ///Gives back the system time of the process
207    double systemTime() const
208    {
209      return stime;
210    }
211    ///Gives back the user time of the process' children
212
213    ///\note On <tt>WIN32</tt> platform this value is not calculated.
214    ///
215    double cUserTime() const
216    {
217      return cutime;
218    }
219    ///Gives back the user time of the process' children
220
221    ///\note On <tt>WIN32</tt> platform this value is not calculated.
222    ///
223    double cSystemTime() const
224    {
225      return cstime;
226    }
227    ///Gives back the real time
228    double realTime() const {return rtime;}
229  };
230
231  TimeStamp operator*(double b,const TimeStamp &t)
232  {
233    return t*b;
234  }
235
236  ///Prints the time counters
237
238  ///Prints the time counters in the following form:
239  ///
240  /// <tt>u: XX.XXs s: XX.XXs cu: XX.XXs cs: XX.XXs real: XX.XXs</tt>
241  ///
242  /// where the values are the
243  /// \li \c u: user cpu time,
244  /// \li \c s: system cpu time,
245  /// \li \c cu: user cpu time of children,
246  /// \li \c cs: system cpu time of children,
247  /// \li \c real: real time.
248  /// \relates TimeStamp
249  /// \note On <tt>WIN32</tt> platform the cummulative values are not
250  /// calculated.
251  inline std::ostream& operator<<(std::ostream& os,const TimeStamp &t)
252  {
253    os << "u: " << t.userTime() <<
254      "s, s: " << t.systemTime() <<
255      "s, cu: " << t.cUserTime() <<
256      "s, cs: " << t.cSystemTime() <<
257      "s, real: " << t.realTime() << "s";
258    return os;
259  }
260
261  ///Class for measuring the cpu time and real time usage of the process
262
263  ///Class for measuring the cpu time and real time usage of the process.
264  ///It is quite easy-to-use, here is a short example.
265  ///\code
266  /// #include<lemon/time_measure.h>
267  /// #include<iostream>
268  ///
269  /// int main()
270  /// {
271  ///
272  ///   ...
273  ///
274  ///   Timer t;
275  ///   doSomething();
276  ///   std::cout << t << '\n';
277  ///   t.restart();
278  ///   doSomethingElse();
279  ///   std::cout << t << '\n';
280  ///
281  ///   ...
282  ///
283  /// }
284  ///\endcode
285  ///
286  ///The \ref Timer can also be \ref stop() "stopped" and
287  ///\ref start() "started" again, so it is possible to compute collected
288  ///running times.
289  ///
290  ///\warning Depending on the operation system and its actual configuration
291  ///the time counters have a certain (10ms on a typical Linux system)
292  ///granularity.
293  ///Therefore this tool is not appropriate to measure very short times.
294  ///Also, if you start and stop the timer very frequently, it could lead to
295  ///distorted results.
296  ///
297  ///\note If you want to measure the running time of the execution of a certain
298  ///function, consider the usage of \ref TimeReport instead.
299  ///
300  ///\sa TimeReport
301  class Timer
302  {
303    int _running; //Timer is running iff _running>0; (_running>=0 always holds)
304    TimeStamp start_time; //This is the relativ start-time if the timer
305                          //is _running, the collected _running time otherwise.
306
307    void _reset() {if(_running) start_time.stamp(); else start_time.reset();}
308
309  public:
310    ///Constructor.
311
312    ///\param run indicates whether or not the timer starts immediately.
313    ///
314    Timer(bool run=true) :_running(run) {_reset();}
315
316    ///\name Control the state of the timer
317    ///Basically a Timer can be either running or stopped,
318    ///but it provides a bit finer control on the execution.
319    ///The \ref lemon::Timer "Timer" also counts the number of
320    ///\ref lemon::Timer::start() "start()" executions, and it stops
321    ///only after the same amount (or more) \ref lemon::Timer::stop()
322    ///"stop()"s. This can be useful e.g. to compute the running time
323    ///of recursive functions.
324
325    ///@{
326
327    ///Reset and stop the time counters
328
329    ///This function resets and stops the time counters
330    ///\sa restart()
331    void reset()
332    {
333      _running=0;
334      _reset();
335    }
336
337    ///Start the time counters
338
339    ///This function starts the time counters.
340    ///
341    ///If the timer is started more than ones, it will remain running
342    ///until the same amount of \ref stop() is called.
343    ///\sa stop()
344    void start()
345    {
346      if(_running) _running++;
347      else {
348        _running=1;
349        TimeStamp t;
350        t.stamp();
351        start_time=t-start_time;
352      }
353    }
354
355
356    ///Stop the time counters
357
358    ///This function stops the time counters. If start() was executed more than
359    ///once, then the same number of stop() execution is necessary the really
360    ///stop the timer.
361    ///
362    ///\sa halt()
363    ///\sa start()
364    ///\sa restart()
365    ///\sa reset()
366
367    void stop()
368    {
369      if(_running && !--_running) {
370        TimeStamp t;
371        t.stamp();
372        start_time=t-start_time;
373      }
374    }
375
376    ///Halt (i.e stop immediately) the time counters
377
378    ///This function stops immediately the time counters, i.e. <tt>t.halt()</tt>
379    ///is a faster
380    ///equivalent of the following.
381    ///\code
382    ///  while(t.running()) t.stop()
383    ///\endcode
384    ///
385    ///
386    ///\sa stop()
387    ///\sa restart()
388    ///\sa reset()
389
390    void halt()
391    {
392      if(_running) {
393        _running=0;
394        TimeStamp t;
395        t.stamp();
396        start_time=t-start_time;
397      }
398    }
399
400    ///Returns the running state of the timer
401
402    ///This function returns the number of stop() exections that is
403    ///necessary to really stop the timer.
404    ///For example the timer
405    ///is running if and only if the return value is \c true
406    ///(i.e. greater than
407    ///zero).
408    int running()  { return _running; }
409
410
411    ///Restart the time counters
412
413    ///This function is a shorthand for
414    ///a reset() and a start() calls.
415    ///
416    void restart()
417    {
418      reset();
419      start();
420    }
421
422    ///@}
423
424    ///\name Query Functions for the ellapsed time
425
426    ///@{
427
428    ///Gives back the ellapsed user time of the process
429    double userTime() const
430    {
431      return operator TimeStamp().userTime();
432    }
433    ///Gives back the ellapsed system time of the process
434    double systemTime() const
435    {
436      return operator TimeStamp().systemTime();
437    }
438    ///Gives back the ellapsed user time of the process' children
439
440    ///\note On <tt>WIN32</tt> platform this value is not calculated.
441    ///
442    double cUserTime() const
443    {
444      return operator TimeStamp().cUserTime();
445    }
446    ///Gives back the ellapsed user time of the process' children
447
448    ///\note On <tt>WIN32</tt> platform this value is not calculated.
449    ///
450    double cSystemTime() const
451    {
452      return operator TimeStamp().cSystemTime();
453    }
454    ///Gives back the ellapsed real time
455    double realTime() const
456    {
457      return operator TimeStamp().realTime();
458    }
459    ///Computes the ellapsed time
460
461    ///This conversion computes the ellapsed time, therefore you can print
462    ///the ellapsed time like this.
463    ///\code
464    ///  Timer t;
465    ///  doSomething();
466    ///  std::cout << t << '\n';
467    ///\endcode
468    operator TimeStamp () const
469    {
470      TimeStamp t;
471      t.stamp();
472      return _running?t-start_time:start_time;
473    }
474
475
476    ///@}
477  };
478
479  ///Same as Timer but prints a report on destruction.
480
481  ///Same as \ref Timer but prints a report on destruction.
482  ///This example shows its usage.
483  ///\code
484  ///  void myAlg(ListGraph &g,int n)
485  ///  {
486  ///    TimeReport tr("Running time of myAlg: ");
487  ///    ... //Here comes the algorithm
488  ///  }
489  ///\endcode
490  ///
491  ///\sa Timer
492  ///\sa NoTimeReport
493  class TimeReport : public Timer
494  {
495    std::string _title;
496    std::ostream &_os;
497  public:
498    ///Constructor
499
500    ///Constructor.
501    ///\param title This text will be printed before the ellapsed time.
502    ///\param os The stream to print the report to.
503    ///\param run Sets whether the timer should start immediately.
504    TimeReport(std::string title,std::ostream &os=std::cerr,bool run=true)
505      : Timer(run), _title(title), _os(os){}
506    ///Destructor that prints the ellapsed time
507    ~TimeReport()
508    {
509      _os << _title << *this << std::endl;
510    }
511  };
512
513  ///'Do nothing' version of TimeReport
514
515  ///\sa TimeReport
516  ///
517  class NoTimeReport
518  {
519  public:
520    ///\e
521    NoTimeReport(std::string,std::ostream &,bool) {}
522    ///\e
523    NoTimeReport(std::string,std::ostream &) {}
524    ///\e
525    NoTimeReport(std::string) {}
526    ///\e Do nothing.
527    ~NoTimeReport() {}
528
529    operator TimeStamp () const { return TimeStamp(); }
530    void reset() {}
531    void start() {}
532    void stop() {}
533    void halt() {}
534    int running() { return 0; }
535    void restart() {}
536    double userTime() const { return 0; }
537    double systemTime() const { return 0; }
538    double cUserTime() const { return 0; }
539    double cSystemTime() const { return 0; }
540    double realTime() const { return 0; }
541  };
542
543  ///Tool to measure the running time more exactly.
544
545  ///This function calls \c f several times and returns the average
546  ///running time. The number of the executions will be choosen in such a way
547  ///that the full real running time will be roughly between \c min_time
548  ///and <tt>2*min_time</tt>.
549  ///\param f the function object to be measured.
550  ///\param min_time the minimum total running time.
551  ///\retval num if it is not \c NULL, then the actual
552  ///        number of execution of \c f will be written into <tt>*num</tt>.
553  ///\retval full_time if it is not \c NULL, then the actual
554  ///        total running time will be written into <tt>*full_time</tt>.
555  ///\return The average running time of \c f.
556
557  template<class F>
558  TimeStamp runningTimeTest(F f,double min_time=10,unsigned int *num = NULL,
559                            TimeStamp *full_time=NULL)
560  {
561    TimeStamp full;
562    unsigned int total=0;
563    Timer t;
564    for(unsigned int tn=1;tn <= 1U<<31 && full.realTime()<=min_time; tn*=2) {
565      for(;total<tn;total++) f();
566      full=t;
567    }
568    if(num) *num=total;
569    if(full_time) *full_time=full;
570    return full/total;
571  }
572
573  /// @}
574
575
576} //namespace lemon
577
578#endif //LEMON_TIME_MEASURE_H
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