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Timer.h
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1 //# Timer.h: measure the time it takes to execute parts of a program
2 //# Copyright (C) 1993,1994,1995,1996,1997,1999,2000,2001
3 //# Associated Universities, Inc. Washington DC, USA.
4 //#
5 //# This library is free software; you can redistribute it and/or modify it
6 //# under the terms of the GNU Library General Public License as published by
7 //# the Free Software Foundation; either version 2 of the License, or (at your
8 //# option) any later version.
9 //#
10 //# This library is distributed in the hope that it will be useful, but WITHOUT
11 //# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 //# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
13 //# License for more details.
14 //#
15 //# You should have received a copy of the GNU Library General Public License
16 //# along with this library; if not, write to the Free Software Foundation,
17 //# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
18 //#
19 //# Correspondence concerning AIPS++ should be addressed as follows:
20 //# Internet email: aips2-request@nrao.edu.
21 //# Postal address: AIPS++ Project Office
22 //# National Radio Astronomy Observatory
23 //# 520 Edgemont Road
24 //# Charlottesville, VA 22903-2475 USA
25 //#
26 //# $Id$
27 
28 #ifndef CASA_TIMER_H
29 #define CASA_TIMER_H
30 
31 
32 #include <casacore/casa/aips.h>
33 #include <sys/types.h>
34 
35 //# Forward declarations
36 #include <casacore/casa/iosfwd.h>
37 
38 #if defined(DOS) || defined(MSDOS)
39 #include <sys/timeb.h>
40 extern "C" {
41 #include <time.h>
42 }
43 
44 #elif defined(AIPS_SOLARIS) || defined(AIPS_IRIX) || defined(AIPS_OSF) || defined(__hpux__) || defined(AIPS_LINUX) || defined(AIPS_DARWIN) || defined(AIPS_BSD) || defined(__GLIBC__)
45  #if defined(AIPS_CRAY_PGI)
46  #include <sys/time.h>
47  #include <sys/resource.h>
48  #include <unistd.h>
49  extern "C" int getrusage(int, struct rusage*);
50  #else
51  #include <sys/times.h>
52  #include <unistd.h>
53  #endif
54 
55 #else
56 #include <sys/timeb.h>
57 #include <sys/time.h>
58 extern "C" int getrusage(int, struct rusage*);
59 extern "C" int ftime(struct timeb*);
60 #include <sys/resource.h>
61 #endif
62 
63 namespace casacore { //# NAMESPACE CASACORE - BEGIN
64 
65 // Class declaration.
66 class String;
67 
68 // <summary> measure the time it takes to execute parts of a program</summary>
69 
70 // <use visibility=export>
71 
72 // <reviewed reviewer="Paul Shannon" date="1995/03/01/ tests="tTimer" demos="">
73 // </reviewed>
74 
75 // <synopsis>
76 // The Timer class provides an interface to system timing. It
77 // allows a C++ program to record the time between a reference
78 // point (mark) and now. This class uses the system time(2)
79 // interface to provide time resolution at either millisecond or
80 // microsecond granularity, depending upon operating system
81 // support and features. Since the time duration is stored in
82 // a 32-bit word, the maximum time period before rollover
83 // occurs is about 71 minutes.
84 //
85 // Due to operating system dependencies, the accuracy of all
86 // member function results may not be as documented. For example
87 // some operating systems do not support timers with
88 // microsecond resolution. In those cases, the values returned
89 // are provided to the nearest millisecond or other unit of
90 // time as appropriate. See the Timer header file for system-
91 // specific notes.
92 //
93 // <note role=tip> This Timer class is based on the TI COOL library
94 // Timer class
95 // </note>
96 // </synopsis>
97 
98 // <example>
99 // Here's how to create a timer, start it (the 'mark' member function)
100 // and display a breakdown. Recall that
101 // <srcblock> realtime = user time + system time
102 // </srcblock>
103 // <srcblock>
104 //
105 // Timer timer; // the mark is set at construction time
106 // timer.mark(); // if you want to restart the clock
107 // ...do some calculation...
108 // cout << "user: " << timer.user () << endl;
109 // cout << "system: " << timer.system () << endl;
110 // cout << "real: " << timer.real () << endl;
111 //
112 // </srcblock>
113 // </example>
114 
115 // <todo asof="1995/03/01">
116 // <li> it might be useful to have a stop () member function: for
117 // really precise timing, the successive calls to user, system
118 // and real all happen at measurably different times
119 // <li> provide an enquiry function that reports the resolution of
120 // the timer
121 // <li> add 'start' member function, a synonym for 'mark' but more
122 // comprehensible
123 //
124 // </todo>
125 
126 
127 class Timer {
128 public:
129  //
130  // Construct a timer and set the mark ("mark()").
131  //
132  Timer() {mark();}
133 
134  //
135  // Set the timer mark -- i.e., start the clock ticking
136  //
137  void mark();
138 
139  //
140  // Get the user time (in seconds) since last "mark()".
141  //
142  double user() const;
143 
144  //
145  // Get the system time (in seconds) since last "mark()".
146  //
147  double system() const;
148 
149  //
150  // Get the user+system time (in seconds) since last "mark()".
151  //
152  double all() const;
153 
154  //
155  // Get the real time (in seconds) since last "mark()".
156  //
157  double real() const;
158 
159  // Show real, user, system time (in seconds) on cout or a user supplied
160  // stream.
161  // <group>
162  void show() const;
163  void show(ostream &os) const;
164  // </group>
165 
166  // Show real, user, system time (in seconds) on cout or a user supplied
167  // stream preceeded by the string parameter.
168  // <group>
169  void show(const String&) const;
170  void show(ostream &os, const String&prefix) const;
171  // </group>
172 
173  //
174  // Get the user time (in microseconds) since last "mark()".
175  //
176  double user_usec() const;
177 
178  //
179  // Get the system time (in microseconds) since last "mark()".
180  //
181  double system_usec() const;
182 
183  //
184  // Get the user+system time (in microseconds) since last "mark()".
185  //
186  double all_usec() const;
187 
188 private:
189 #if defined(DOS) || defined(MSDOS)
190  clock_t usage0;
191  timeb real0; //# elapsed real time at last mark
192 #elif defined(AIPS_SOLARIS) || defined(AIPS_IRIX) || defined(AIPS_OSF) || defined(__hpux__) || defined(AIPS_LINUX) || defined(AIPS_DARWIN) || defined(AIPS_BSD) || defined(__GLIBC__)
193  #if defined(AIPS_CRAY_PGI)
194  //struct timeval usage0;
195  rusage usage0; //# rusage structure at last mark
196  struct timeval real0; //# elapsed real time at last mark
197  #else
198  tms usage0; //# tms structure at last mark
199  clock_t real0; //# elapsed real time at last mark
200  #endif
201 #else
202  rusage usage0; //# rusage structure at last mark
203  timeb real0; //# elapsed real time at last mark
204 #endif
205 };
206 
207 
208 } //# NAMESPACE CASACORE - END
209 
210 #endif
void show() const
Show real, user, system time (in seconds) on cout or a user supplied stream.
Timer()
Construct a timer and set the mark (&quot;mark()&quot;).
Definition: Timer.h:132
double all_usec() const
Get the user+system time (in microseconds) since last &quot;mark()&quot;.
int ftime(struct timeb *)
double user_usec() const
Get the user time (in microseconds) since last &quot;mark()&quot;.
measure the time it takes to execute parts of a program
Definition: Timer.h:127
void mark()
Set the timer mark – i.e., start the clock ticking.
int getrusage(int, struct rusage *)
double system() const
Get the system time (in seconds) since last &quot;mark()&quot;.
double all() const
Get the user+system time (in seconds) since last &quot;mark()&quot;.
String: the storage and methods of handling collections of characters.
Definition: String.h:223
timeb real0
Definition: Timer.h:203
double system_usec() const
Get the system time (in microseconds) since last &quot;mark()&quot;.
double user() const
Get the user time (in seconds) since last &quot;mark()&quot;.
rusage usage0
Definition: Timer.h:202
double real() const
Get the real time (in seconds) since last &quot;mark()&quot;.
#define casacore
&lt;X11/Intrinsic.h&gt; #defines true, false, casacore::Bool, and String.
Definition: X11Intrinsic.h:42