alpar@906: /* -*- C++ -*-
ladanyi@1435:  * lemon/time_measure.h - Part of LEMON, a generic C++ optimization library
alpar@906:  *
alpar@1164:  * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
alpar@1359:  * (Egervary Research Group on Combinatorial Optimization, EGRES).
alpar@906:  *
alpar@906:  * Permission to use, modify and distribute this software is granted
alpar@906:  * provided that this copyright notice appears in all copies. For
alpar@906:  * precise terms see the accompanying LICENSE file.
alpar@906:  *
alpar@906:  * This software is provided "AS IS" with no warranty of any kind,
alpar@906:  * express or implied, and with no claim as to its suitability for any
alpar@906:  * purpose.
alpar@906:  *
alpar@906:  */
alpar@906: 
alpar@921: #ifndef LEMON_TIME_MEASURE_H
alpar@921: #define LEMON_TIME_MEASURE_H
alpar@428: 
klao@491: ///\ingroup misc
alpar@428: ///\file
alpar@428: ///\brief Tools for measuring cpu usage
alpar@428: 
alpar@428: #include <sys/time.h>
alpar@428: #include <sys/times.h>
alpar@428: #include <fstream>
alpar@428: #include <iostream>
alpar@428: #include <unistd.h>
alpar@428: 
alpar@921: namespace lemon {
alpar@428: 
alpar@428:   /// \addtogroup misc
alpar@428:   /// @{
alpar@428: 
alpar@428:   /// A class to store (cpu)time instances.
alpar@428: 
alpar@428:   /// This class stores five time values.
alpar@428:   /// - a real time
alpar@428:   /// - a user cpu time
alpar@428:   /// - a system cpu time
alpar@428:   /// - a user cpu time of children
alpar@428:   /// - a system cpu time of children
alpar@428:   ///
alpar@428:   /// TimeStamp's can be added to or substracted from each other and
alpar@428:   /// they can be pushed to a stream.
alpar@458:   ///
alpar@458:   /// In most cases, perhaps \ref Timer class is what you want to use instead.
alpar@458:   ///
alpar@458:   ///\author Alpar Juttner
alpar@428: 
alpar@428:   class TimeStamp
alpar@428:   {
alpar@1689:     struct rtms 
alpar@1689:     {
alpar@1689:       double tms_utime;
alpar@1689:       double tms_stime;
alpar@1689:       double tms_cutime;
alpar@1689:       double tms_cstime;
alpar@1689:       rtms() {}
alpar@1689:       rtms(tms ts) : tms_utime(ts.tms_utime), tms_stime(ts.tms_stime),
alpar@1689: 		     tms_cutime(ts.tms_cutime), tms_cstime(ts.tms_cstime) {}
alpar@1689:     };
alpar@1689:     rtms ts;
alpar@428:     double real_time;
alpar@428:   
alpar@1689:     rtms &getTms() {return ts;}
alpar@1689:     const rtms &getTms() const {return ts;}
alpar@1689: 
alpar@1780:     void _reset() 
alpar@1780:     { ts.tms_utime=ts.tms_stime=ts.tms_cutime=ts.tms_cstime=0; real_time=0;}
alpar@1780: 
alpar@428:   public:
alpar@428: 
alpar@428:     ///Read the current time values of the process
alpar@428:     void stamp()
alpar@428:     {
alpar@428:       timeval tv;
alpar@1689:       tms _ts;
alpar@1689:       times(&_ts);
alpar@428:       gettimeofday(&tv, 0);real_time=tv.tv_sec+double(tv.tv_usec)/1e6;
alpar@1689:       ts=_ts;
alpar@428:     }
alpar@428:   
alpar@428:     /// Constructor initializing with zero
alpar@428:     TimeStamp()
alpar@1780:     { _reset(); }
alpar@428:     ///Constructor initializing with the current time values of the process
alpar@428:     TimeStamp(void *) { stamp();}
alpar@428:   
alpar@1780:     ///Set every time value to zero
alpar@1780:     TimeStamp &reset() {_reset();return *this;}
alpar@1780: 
alpar@1005:     ///\e
alpar@428:     TimeStamp &operator+=(const TimeStamp &b)
alpar@428:     {
alpar@428:       ts.tms_utime+=b.ts.tms_utime;
alpar@428:       ts.tms_stime+=b.ts.tms_stime;
alpar@428:       ts.tms_cutime+=b.ts.tms_cutime;
alpar@428:       ts.tms_cstime+=b.ts.tms_cstime;
alpar@428:       real_time+=b.real_time;
alpar@428:       return *this;
alpar@428:     }
alpar@1005:     ///\e
alpar@428:     TimeStamp operator+(const TimeStamp &b) const
alpar@428:     {
alpar@428:       TimeStamp t(*this);
alpar@428:       return t+=b;
alpar@428:     }
alpar@1005:     ///\e
alpar@428:     TimeStamp &operator-=(const TimeStamp &b)
alpar@428:     {
alpar@428:       ts.tms_utime-=b.ts.tms_utime;
alpar@428:       ts.tms_stime-=b.ts.tms_stime;
alpar@428:       ts.tms_cutime-=b.ts.tms_cutime;
alpar@428:       ts.tms_cstime-=b.ts.tms_cstime;
alpar@428:       real_time-=b.real_time;
alpar@428:       return *this;
alpar@428:     }
alpar@1005:     ///\e
alpar@428:     TimeStamp operator-(const TimeStamp &b) const
alpar@428:     {
alpar@428:       TimeStamp t(*this);
alpar@428:       return t-=b;
alpar@428:     }
alpar@1689:     ///\e
alpar@1689:     TimeStamp &operator*=(double b)
alpar@1689:     {
alpar@1689:       ts.tms_utime*=b;
alpar@1689:       ts.tms_stime*=b;
alpar@1689:       ts.tms_cutime*=b;
alpar@1689:       ts.tms_cstime*=b;
alpar@1689:       real_time*=b;
alpar@1689:       return *this;
alpar@1689:     }
alpar@1689:     ///\e
alpar@1689:     TimeStamp operator*(double b) const
alpar@1689:     {
alpar@1689:       TimeStamp t(*this);
alpar@1689:       return t*=b;
alpar@1689:     }
alpar@1689:     friend TimeStamp operator*(double b,const TimeStamp &t);
alpar@1689:     ///\e
alpar@1689:     TimeStamp &operator/=(double b)
alpar@1689:     {
alpar@1689:       ts.tms_utime/=b;
alpar@1689:       ts.tms_stime/=b;
alpar@1689:       ts.tms_cutime/=b;
alpar@1689:       ts.tms_cstime/=b;
alpar@1689:       real_time/=b;
alpar@1689:       return *this;
alpar@1689:     }
alpar@1689:     ///\e
alpar@1689:     TimeStamp operator/(double b) const
alpar@1689:     {
alpar@1689:       TimeStamp t(*this);
alpar@1689:       return t/=b;
alpar@1689:     }
alpar@428:     ///The time ellapsed since the last call of stamp()
alpar@428:     TimeStamp ellapsed() const
alpar@428:     {
alpar@428:       TimeStamp t(NULL);
alpar@428:       return t-*this;
alpar@428:     }
alpar@428:   
alpar@428:     friend std::ostream& operator<<(std::ostream& os,const TimeStamp &t);
alpar@428:   
alpar@428:     ///Gives back the user time of the process
alpar@1689:     double userTime() const
alpar@428:     {
alpar@428:       return double(ts.tms_utime)/sysconf(_SC_CLK_TCK);
alpar@428:     }
alpar@428:     ///Gives back the system time of the process
alpar@1689:     double systemTime() const
alpar@428:     {
alpar@428:       return double(ts.tms_stime)/sysconf(_SC_CLK_TCK);
alpar@428:     }
alpar@428:     ///Gives back the user time of the process' children
alpar@1689:     double cUserTime() const
alpar@428:     {
alpar@428:       return double(ts.tms_cutime)/sysconf(_SC_CLK_TCK);
alpar@428:     }
alpar@428:     ///Gives back the user time of the process' children
alpar@1689:     double cSystemTime() const
alpar@428:     {
alpar@428:       return double(ts.tms_cstime)/sysconf(_SC_CLK_TCK);
alpar@428:     }
alpar@1780:     ///Gives back the real time
alpar@1689:     double realTime() const {return real_time;}
alpar@428:   };
alpar@428: 
alpar@1689:   TimeStamp operator*(double b,const TimeStamp &t) 
alpar@1689:   {
alpar@1689:     return t*b;
alpar@1689:   }
alpar@1689:   
alpar@1780:   ///Class for measuring the cpu time and real time usage of the process
alpar@458: 
alpar@1780:   ///Class for measuring the cpu time and real time usage of the process.
alpar@458:   ///It is quite easy-to-use, here is a short example.
alpar@458:   ///\code
alpar@921:   ///#include<lemon/time_measure.h>
alpar@696:   ///#include<iostream>
alpar@814:   ///
alpar@458:   ///int main()
alpar@458:   ///{
alpar@458:   ///
alpar@458:   ///  ...
alpar@458:   ///
alpar@696:   ///  Timer T;
alpar@458:   ///  doSomething();
alpar@696:   ///  std::cout << T << '\n';
alpar@458:   ///  T.reset();
alpar@458:   ///  doSomethingElse();
alpar@696:   ///  std::cout << T << '\n';
alpar@458:   ///
alpar@458:   ///  ...
alpar@458:   ///
alpar@458:   ///}
alpar@458:   ///\endcode
alpar@458:   ///
alpar@1780:   ///The \ref Timer can also be \ref stop() "stopped" and
alpar@1780:   ///\ref start() "started" again, so it is easy to compute collected
alpar@1780:   ///running times.
alpar@1780:   ///
alpar@1780:   ///\warning Depending on the operation system and its actual configuration
alpar@1780:   ///the time counters have a certain (relatively big) granularity.
alpar@1780:   ///Therefore this tool is not appropriate to measure very short times.
alpar@1780:   ///Also, if you start and stop the timer very frequently, it could lead
alpar@1780:   ///distorted results.
alpar@1780:   ///
alpar@1780:   ///The \ref Timer also counts the number of \ref start()
alpar@1780:   ///executions, and is stops only after the same amount (or more)
alpar@1780:   ///\ref stop() "stop()"s. This can be useful e.g. to compute the running time
alpar@1780:   ///of recursive functions.
alpar@1780:   ///
alpar@458:   ///\todo This shouldn't be Unix (Linux) specific.
alpar@458:   ///
alpar@458:   ///\author Alpar Juttner
alpar@428:   class Timer
alpar@428:   {
alpar@1780:     int running; //Timer is running iff running>0; (running>=0 always holds)
alpar@1780:     TimeStamp start_time; //This is the relativ start-time if the timer
alpar@1780:                           //is running, the collected running time otherwise.
alpar@1780:     
alpar@1780:     void _reset() {if(running) start_time.stamp(); else start_time.reset();}
alpar@428:   
alpar@428:   public: 
alpar@1780:     ///Constructor.
alpar@1780: 
alpar@1780:     ///\param _running indicates whether or not the timer starts immediately.
alpar@1780:     ///
alpar@1780:     Timer(bool _running=true) :running(_running) {_reset();}
alpar@428: 
alpar@428:     ///Computes the ellapsed time
alpar@428: 
alpar@428:     ///This conversion computes the ellapsed time
alpar@1780:     ///
alpar@1005:     operator TimeStamp () const
alpar@428:     {
alpar@428:       TimeStamp t;
alpar@428:       t.stamp();
alpar@1780:       return running?t-start_time:start_time;
alpar@428:     }
alpar@428: 
alpar@428:     ///Resets the time counters
alpar@1069: 
alpar@1069:     ///Resets the time counters
alpar@1069:     ///
alpar@1069:     void reset()
alpar@428:     {
alpar@428:       _reset();
alpar@428:     }
alpar@1005: 
alpar@1780:     ///Start the time counters
alpar@1780:     
alpar@1780:     ///This function starts the time counters.
alpar@1780:     ///
alpar@1780:     ///If the timer is started more than ones, it will remain running
alpar@1780:     ///until the same amount of \ref stop() is called.
alpar@1780:     ///\sa stop()
alpar@1780:     void start() 
alpar@1780:     {
alpar@1780:       if(running) running++;
alpar@1780:       else {
alpar@1780: 	TimeStamp t;
alpar@1780: 	t.stamp();
alpar@1780: 	start_time=t-start_time;
alpar@1780:       }
alpar@1780:     }
alpar@1780:     
alpar@1780:     ///Stop the time counters
alpar@1005: 
alpar@1780:     ///This function stops the time counters.
alpar@1780:     ///
alpar@1780:     ///\sa stop()
alpar@1780:     void stop() 
alpar@1780:     {
alpar@1780:       if(running && !--running) {
alpar@1780: 	TimeStamp t;
alpar@1780: 	t.stamp();
alpar@1780: 	start_time=t-start_time;
alpar@1780:       }
alpar@1780:     }
alpar@1780:     
alpar@1005:     ///Gives back the ellapsed user time of the process
alpar@1689:     double userTime() const
alpar@1005:     {
alpar@1689:       return operator TimeStamp().userTime();
alpar@1005:     }
alpar@1005:     ///Gives back the ellapsed system time of the process
alpar@1689:     double systemTime() const
alpar@1005:     {
alpar@1689:       return operator TimeStamp().systemTime();
alpar@1005:     }
alpar@1005:     ///Gives back the ellapsed user time of the process' children
alpar@1689:     double cUserTime() const
alpar@1005:     {
alpar@1689:       return operator TimeStamp().cUserTime();
alpar@1005:     }
alpar@1005:     ///Gives back the ellapsed user time of the process' children
alpar@1689:     double cSystemTime() const
alpar@1005:     {
alpar@1689:       return operator TimeStamp().cSystemTime();
alpar@1005:     }
alpar@1780:     ///Gives back the ellapsed real time
alpar@1689:     double realTime() const
alpar@1005:     {
alpar@1689:       return operator TimeStamp().realTime();
alpar@1005:     }
alpar@1005: 
alpar@428:   };
alpar@428: 
alpar@428:   ///Prints the time counters
alpar@428: 
klao@492:   ///Prints the time counters in the following form:
alpar@428:   ///
alpar@440:   /// <tt>u: XX.XXs s: XX.XXs cu: XX.XXs cs: XX.XXs real: XX.XXs</tt>
alpar@428:   ///
alpar@428:   /// where the values are the
alpar@440:   /// \li \c u: user cpu time,
alpar@440:   /// \li \c s: system cpu time,
alpar@440:   /// \li \c cu: user cpu time of children,
alpar@440:   /// \li \c cs: system cpu time of children,
alpar@440:   /// \li \c real: real time.
alpar@814:   /// \relates TimeStamp
alpar@428:   inline std::ostream& operator<<(std::ostream& os,const TimeStamp &t)
alpar@428:   {
alpar@428:     long cls = sysconf(_SC_CLK_TCK);
alpar@428:     os << "u: " << double(t.getTms().tms_utime)/cls <<
alpar@428:       "s, s: " << double(t.getTms().tms_stime)/cls <<
alpar@428:       "s, cu: " << double(t.getTms().tms_cutime)/cls <<
alpar@428:       "s, cs: " << double(t.getTms().tms_cstime)/cls <<
alpar@1689:       "s, real: " << t.realTime() << "s";
alpar@428:     return os;
alpar@428:   }
alpar@428: 
alpar@1689:   
alpar@1689:   ///Tool to measure the running time more exactly.
alpar@1689:   
alpar@1689:   ///This function calls \c f several times and returns the average
alpar@1689:   ///running time. The number of the executions will be choosen in such a way
alpar@1780:   ///that the full real running time will be roughly between \c min_time
alpar@1689:   ///and <tt>2*min_time</tt>.
alpar@1689:   ///\param f the function object to be measured.
alpar@1689:   ///\param min_time the minimum total running time.
alpar@1689:   ///\retval num if it is not \c NULL, then *num will contain the actual
alpar@1689:   ///        number of execution of \c f.
alpar@1689:   ///\retval full_time if it is not \c NULL, then *full_time
alpar@1689:   ///        will contain the actual
alpar@1689:   ///        total running time.
alpar@1689:   ///\return The average running time of \c f.
alpar@1689:   
alpar@1689:   template<class F>
alpar@1689:   TimeStamp runningTimeTest(F &f,double min_time=10,int *num = NULL,
alpar@1689: 			TimeStamp *full_time=NULL)
alpar@1689:   {
alpar@1689:     Timer t;
alpar@1689:     TimeStamp full;
alpar@1689:     int total=0;
alpar@1689:     for(int tn=1;tn < 1<<24; tn*=2) {
alpar@1689:       for(;total<tn;total++) f();
alpar@1689:       full=t;
alpar@1689:       if(full.realTime()>min_time) {
alpar@1689: 	if(num) *num=total;
alpar@1689: 	if(full_time) *full_time=full;
alpar@1689:       return full/total;
alpar@1689:       }
alpar@1689:     }
alpar@1689:     return TimeStamp();
alpar@1689:   }
alpar@1689:   
alpar@428:   /// @}  
alpar@428: 
alpar@1689: 
alpar@921: } //namespace lemon
alpar@428: 
alpar@921: #endif //LEMON_TIME_MEASURE_H