COIN-OR::LEMON - Graph Library

source: lemon-1.0/lemon/time_measure.h @ 143:c3b45bb643b0

Last change on this file since 143:c3b45bb643b0 was 143:c3b45bb643b0, checked in by Alpar Juttner <alpar@…>, 11 years ago

Resolve several MSVC related compilation problems

File size: 14.1 KB
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[119]1/* -*- C++ -*-
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
[126]26#ifdef WIN32
[143]27#define WIN32_LEAN_AND_MEAN
28#define NOMINMAX
[126]29#include <windows.h>
30#include <cmath>
31#else
[119]32#include <sys/times.h>
[126]33#include <sys/time.h>
34#endif
[119]35
[143]36#include <string>
[119]37#include <fstream>
38#include <iostream>
39
40namespace lemon {
41
42  /// \addtogroup timecount
43  /// @{
44
45  /// A class to store (cpu)time instances.
46
47  /// This class stores five time values.
48  /// - a real time
49  /// - a user cpu time
50  /// - a system cpu time
51  /// - a user cpu time of children
52  /// - a system cpu time of children
53  ///
54  /// TimeStamp's can be added to or substracted from each other and
55  /// they can be pushed to a stream.
56  ///
57  /// In most cases, perhaps the \ref Timer or the \ref TimeReport
58  /// class is what you want to use instead.
59  ///
60  ///\author Alpar Juttner
61
62  class TimeStamp
63  {
[126]64    double utime;
65    double stime;
66    double cutime;
67    double cstime;
68    double rtime;
[119]69 
70    void _reset() {
[126]71      utime = stime = cutime = cstime = rtime = 0;
[119]72    }
73
74  public:
75
76    ///Read the current time values of the process
77    void stamp()
78    {
[126]79#ifndef WIN32
[119]80      timeval tv;
[126]81      gettimeofday(&tv, 0);
82      rtime=tv.tv_sec+double(tv.tv_usec)/1e6;
83
84      tms ts;
85      double tck=sysconf(_SC_CLK_TCK);
86      times(&ts);
87      utime=ts.tms_utime/tck;
88      stime=ts.tms_stime/tck;
89      cutime=ts.tms_cutime/tck;
90      cstime=ts.tms_cstime/tck;
91#else
92      static const double ch = 4294967296.0e-7;
93      static const double cl = 1.0e-7;
94
95      FILETIME system;
96      GetSystemTimeAsFileTime(&system);
97      rtime = ch * system.dwHighDateTime + cl * system.dwLowDateTime;
98
99      FILETIME create, exit, kernel, user;
100      if (GetProcessTimes(GetCurrentProcess(),&create, &exit, &kernel, &user)) {
101        utime = ch * user.dwHighDateTime + cl * user.dwLowDateTime;
102        stime = ch * kernel.dwHighDateTime + cl * kernel.dwLowDateTime;
103        cutime = 0;
104        cstime = 0;
105      } else {
106        rtime = 0;
107        utime = 0;
108        stime = 0;
109        cutime = 0;
110        cstime = 0;
111      }
112#endif     
[119]113    }
114 
115    /// Constructor initializing with zero
116    TimeStamp()
117    { _reset(); }
118    ///Constructor initializing with the current time values of the process
119    TimeStamp(void *) { stamp();}
120 
121    ///Set every time value to zero
122    TimeStamp &reset() {_reset();return *this;}
123
124    ///\e
125    TimeStamp &operator+=(const TimeStamp &b)
126    {
[126]127      utime+=b.utime;
128      stime+=b.stime;
129      cutime+=b.cutime;
130      cstime+=b.cstime;
131      rtime+=b.rtime;
[119]132      return *this;
133    }
134    ///\e
135    TimeStamp operator+(const TimeStamp &b) const
136    {
137      TimeStamp t(*this);
138      return t+=b;
139    }
140    ///\e
141    TimeStamp &operator-=(const TimeStamp &b)
142    {
[126]143      utime-=b.utime;
144      stime-=b.stime;
145      cutime-=b.cutime;
146      cstime-=b.cstime;
147      rtime-=b.rtime;
[119]148      return *this;
149    }
150    ///\e
151    TimeStamp operator-(const TimeStamp &b) const
152    {
153      TimeStamp t(*this);
154      return t-=b;
155    }
156    ///\e
157    TimeStamp &operator*=(double b)
158    {
[126]159      utime*=b;
160      stime*=b;
161      cutime*=b;
162      cstime*=b;
163      rtime*=b;
[119]164      return *this;
165    }
166    ///\e
167    TimeStamp operator*(double b) const
168    {
169      TimeStamp t(*this);
170      return t*=b;
171    }
172    friend TimeStamp operator*(double b,const TimeStamp &t);
173    ///\e
174    TimeStamp &operator/=(double b)
175    {
[126]176      utime/=b;
177      stime/=b;
178      cutime/=b;
179      cstime/=b;
180      rtime/=b;
[119]181      return *this;
182    }
183    ///\e
184    TimeStamp operator/(double b) const
185    {
186      TimeStamp t(*this);
187      return t/=b;
188    }
189    ///The time ellapsed since the last call of stamp()
190    TimeStamp ellapsed() const
191    {
192      TimeStamp t(NULL);
193      return t-*this;
194    }
195 
196    friend std::ostream& operator<<(std::ostream& os,const TimeStamp &t);
197 
198    ///Gives back the user time of the process
199    double userTime() const
200    {
[126]201      return utime;
[119]202    }
203    ///Gives back the system time of the process
204    double systemTime() const
205    {
[126]206      return stime;
[119]207    }
208    ///Gives back the user time of the process' children
[126]209
210    ///\note On <tt>WIN32</tt> platform this value is not calculated.
211    ///
[119]212    double cUserTime() const
213    {
[126]214      return cutime;
[119]215    }
216    ///Gives back the user time of the process' children
[126]217
218    ///\note On <tt>WIN32</tt> platform this value is not calculated.
219    ///
[119]220    double cSystemTime() const
221    {
[126]222      return cstime;
[119]223    }
224    ///Gives back the real time
[126]225    double realTime() const {return rtime;}
[119]226  };
227
228  TimeStamp operator*(double b,const TimeStamp &t)
229  {
230    return t*b;
231  }
232 
233  ///Prints the time counters
234
235  ///Prints the time counters in the following form:
236  ///
237  /// <tt>u: XX.XXs s: XX.XXs cu: XX.XXs cs: XX.XXs real: XX.XXs</tt>
238  ///
239  /// where the values are the
240  /// \li \c u: user cpu time,
241  /// \li \c s: system cpu time,
242  /// \li \c cu: user cpu time of children,
243  /// \li \c cs: system cpu time of children,
244  /// \li \c real: real time.
245  /// \relates TimeStamp
[126]246  /// \note On <tt>WIN32</tt> platform the cummulative values are not
247  /// calculated.
[119]248  inline std::ostream& operator<<(std::ostream& os,const TimeStamp &t)
249  {
[126]250    os << "u: " << t.userTime() <<
251      "s, s: " << t.systemTime() <<
252      "s, cu: " << t.cUserTime() <<
253      "s, cs: " << t.cSystemTime() <<
[119]254      "s, real: " << t.realTime() << "s";
255    return os;
256  }
257
258  ///Class for measuring the cpu time and real time usage of the process
259
260  ///Class for measuring the cpu time and real time usage of the process.
261  ///It is quite easy-to-use, here is a short example.
262  ///\code
263  /// #include<lemon/time_measure.h>
264  /// #include<iostream>
265  ///
266  /// int main()
267  /// {
268  ///
269  ///   ...
270  ///
271  ///   Timer t;
272  ///   doSomething();
273  ///   std::cout << t << '\n';
274  ///   t.restart();
275  ///   doSomethingElse();
276  ///   std::cout << t << '\n';
277  ///
278  ///   ...
279  ///
280  /// }
281  ///\endcode
282  ///
283  ///The \ref Timer can also be \ref stop() "stopped" and
284  ///\ref start() "started" again, so it is possible to compute collected
285  ///running times.
286  ///
287  ///\warning Depending on the operation system and its actual configuration
288  ///the time counters have a certain (10ms on a typical Linux system)
289  ///granularity.
290  ///Therefore this tool is not appropriate to measure very short times.
291  ///Also, if you start and stop the timer very frequently, it could lead to
292  ///distorted results.
293  ///
294  ///\note If you want to measure the running time of the execution of a certain
295  ///function, consider the usage of \ref TimeReport instead.
296  ///
297  ///\todo This shouldn't be Unix (Linux) specific.
298  ///\sa TimeReport
299  ///
300  ///\author Alpar Juttner
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 Timer also counts the number of \ref start()
320    ///executions, and is stops only after the same amount (or more)
321    ///\ref stop() "stop()"s. This can be useful e.g. to compute the running time
322    ///of recursive functions.
323    ///
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
[120]378    ///This function stops immediately the time counters, i.e. <tt>t.halt()</tt>
[119]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
[126]439
440    ///\note On <tt>WIN32</tt> platform this value is not calculated.
441    ///
[119]442    double cUserTime() const
443    {
444      return operator TimeStamp().cUserTime();
445    }
446    ///Gives back the ellapsed user time of the process' children
[126]447
448    ///\note On <tt>WIN32</tt> platform this value is not calculated.
449    ///
[119]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 \ref 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  ///\todo There is no test case for this
494  class TimeReport : public Timer
495  {
496    std::string _title;
497    std::ostream &_os;
498  public:
499    ///\e
500
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
505    TimeReport(std::string title,std::ostream &os=std::cerr,bool run=true)
506      : Timer(run), _title(title), _os(os){}
507    ///\e Prints the ellapsed time on destruction.
508    ~TimeReport()
509    {
510      _os << _title << *this << std::endl;
511    }
512  };
513     
514  ///'Do nothing' version of \ref TimeReport
515
516  ///\sa TimeReport
517  ///
518  class NoTimeReport
519  {
520  public:
521    ///\e
522    NoTimeReport(std::string,std::ostream &,bool) {}
523    ///\e
524    NoTimeReport(std::string,std::ostream &) {}
525    ///\e
526    NoTimeReport(std::string) {}
527    ///\e Do nothing.
528    ~NoTimeReport() {}
529
530    operator TimeStamp () const { return TimeStamp(); }
531    void reset() {}
532    void start() {}
533    void stop() {}
534    void halt() {}
535    int running() { return 0; }
536    void restart() {}
537    double userTime() const { return 0; }
538    double systemTime() const { return 0; }
539    double cUserTime() const { return 0; }
540    double cSystemTime() const { return 0; }
541    double realTime() const { return 0; }
542  };
543     
544  ///Tool to measure the running time more exactly.
545 
546  ///This function calls \c f several times and returns the average
547  ///running time. The number of the executions will be choosen in such a way
548  ///that the full real running time will be roughly between \c min_time
549  ///and <tt>2*min_time</tt>.
550  ///\param f the function object to be measured.
551  ///\param min_time the minimum total running time.
552  ///\retval num if it is not \c NULL, then the actual
553  ///        number of execution of \c f will be written into <tt>*num</tt>.
554  ///\retval full_time if it is not \c NULL, then the actual
555  ///        total running time will be written into <tt>*full_time</tt>.
556  ///\return The average running time of \c f.
557 
558  template<class F>
559  TimeStamp runningTimeTest(F f,double min_time=10,unsigned int *num = NULL,
560                            TimeStamp *full_time=NULL)
561  {
562    TimeStamp full;
563    unsigned int total=0;
564    Timer t;
565    for(unsigned int tn=1;tn <= 1U<<31 && full.realTime()<=min_time; tn*=2) {
566      for(;total<tn;total++) f();
567      full=t;
568    }
569    if(num) *num=total;
570    if(full_time) *full_time=full;
571    return full/total;
572  }
573 
574  /// @} 
575
576
577} //namespace lemon
578
579#endif //LEMON_TIME_MEASURE_H
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