1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
/* -*- C++ -*- */
// $Id$
// ============================================================================
//
// = LIBRARY
// ace
//
// = FILENAME
// High_Res_Timer.h
//
// = AUTHOR
// Doug Schmidt
//
// ============================================================================
#ifndef ACE_HIGH_RES_TIMER_H
#define ACE_HIGH_RES_TIMER_H
#include "ace/ACE.h"
#if !defined (ACE_LACKS_PRAGMA_ONCE)
# pragma once
#endif /* ACE_LACKS_PRAGMA_ONCE */
class ACE_Export ACE_High_Res_Timer
{
// = TITLE
// A high resolution timer class wrapper that encapsulates
// OS-specific high-resolution timers, such as those found on
// Solaris, AIX, Win32/Pentium, and VxWorks.
//
// = DESCRIPTION
// Most of the member functions don't return values. The only
// reason that one would fail is if high-resolution time isn't
// supported on the platform. To avoid impacting performance and
// complicating the interface, in that case, ACE_OS::gettimeofday ()
// is used instead.
//
// The global scale factor is required for platforms that have
// high-resolution timers that return units other than
// microseconds, such as clock ticks. It is represented as a
// static u_long, can only be accessed through static methods,
// and is used by all instances of High Res Timer. The member
// functions that return or print times use the global scale
// factor. They divide the "time" that they get from
// ACE_OS::gethrtime () by global_scale_factor_ to obtain the
// time in microseconds. Its units are therefore 1/microsecond.
// On Solaris, a scale factor of 1000 should be used because its
// high-resolution timer returns nanoseconds. However, on Intel
// platforms, we use RDTSC which returns the number of clock
// ticks since system boot. For a 200MHz cpu, each clock tick
// is 1/200 of a microsecond; the global_scale_factor_ should
// therefore be 200.
//
// NOTE: the elapsed time calculations in the print methods use
// ACE_hrtime_t values. Those methods do _not_ check for overflow!
//
// NOTE: Gabe <begeddov@proaxis.com> raises this issue
// regarding ACE_OS::gethrtime (): on multi-processors, the
// processor that you query for your timer.stop () value might
// not be the one you queried for timer.start (). Its not clear
// how much divergence there would be, if any.
//
// This issue is not mentioned in the Solaris 2.5.1 gethrtime
// man page.
public:
// = Initialization method.
static void global_scale_factor (ACE_UINT32 gsf);
// global_scale_factor_ is set to <gsf>. All High_Res_Timers use
// global_scale_factor_. This allows applications to set the scale
// factor just once for all High_Res_Timers. Check
// High_Res_Timer.cpp for the default global_scale_factors for
// several platforms. For many platforms (e.g., Solaris), the
// global_scale_factor_ is set to 1000 so that <scale_factor> need
// not be set. Careful, a <scale_factor> of 0 will cause division
// by zero exceptions.
static ACE_UINT32 global_scale_factor ();
// Accesses the global_scale_factor.
static int get_env_global_scale_factor (const char *env = "ACE_SCALE_FACTOR");
// Sets the global_scale_factor to the value in the <env>
// environment variable. Returns 0 on success, -1 on failure. Note
// if <env> points to string "0" (value zero), this call will fail.
// This is basically a no-op on CE because there is no concept of
// environment variable on CE.
static ACE_UINT32 calibrate (const ACE_UINT32 usec = 500000,
const u_int iterations = 10);
// Set (and return, for info) the global scale factor by sleeping
// for <usec> and counting the number of intervening clock cycles.
// Average over <iterations> of <usec> each. On some platforms,
// such as Pentiums, this is called automatically during the first
// ACE_High_Res_Timer construction with the default parameter
// values. An application can override that by calling calibrate
// with any desired parameter values _prior_ to constructing the
// first ACE_High_Res_Timer instance.
ACE_High_Res_Timer (void);
// Initialize the timer.
~ACE_High_Res_Timer (void);
// dtor.
void reset (void);
// Reinitialize the timer.
void start (const ACE_OS::ACE_HRTimer_Op = ACE_OS::ACE_HRTIMER_GETTIME);
// Start timing.
void stop (const ACE_OS::ACE_HRTimer_Op = ACE_OS::ACE_HRTIMER_GETTIME);
// Stop timing.
void elapsed_time (ACE_Time_Value &tv) const;
// Set <tv> to the number of microseconds elapsed.
void elapsed_time (ACE_hrtime_t &nanoseconds) const;
// Set <nanoseconds> to the number of nanoseconds elapsed.
#if defined (ACE_HAS_POSIX_TIME)
void elapsed_time (struct timespec &) const;
// Returns the elapsed (stop - start) time in a struct timespec
// (sec, nsec).
#endif /* ACE_HAS_POSIX_TIME */
void elapsed_microseconds (ACE_hrtime_t &usecs) const;
// Sets <usecs> to the elapsed (stop - start) time in microseconds.
void start_incr (const ACE_OS::ACE_HRTimer_Op = ACE_OS::ACE_HRTIMER_GETTIME);
// Start incremental timing.
void stop_incr (const ACE_OS::ACE_HRTimer_Op = ACE_OS::ACE_HRTIMER_GETTIME);
// Stop incremental timing.
void elapsed_time_incr (ACE_Time_Value &tv) const;
// Set <tv> to the number of microseconds elapsed between all
// calls to start_incr and stop_incr.
void elapsed_time_incr (ACE_hrtime_t &nanoseconds) const;
// Set <nsec> to the number of nanoseconds elapsed between all
// calls to start_incr and stop_incr.
#if !defined (ACE_HAS_WINCE)
// @@ These two functions are currently not supported on Windows CE.
// However, we should probably use the handle and ACE_Log_Msg to
// print out the result.
void print_total (const char *message,
const int iterations = 1,
ACE_HANDLE handle = ACE_STDOUT) const;
// Print total time. NOTE: only use print_total ()
// if incremental timings had been used!
void print_ave (const char *message,
const int iterations = 1,
ACE_HANDLE handle = ACE_STDOUT) const;
// Print average time.
#endif /* !ACE_HAS_WINCE */
void dump (void) const;
// Dump the state of an object.
ACE_ALLOC_HOOK_DECLARE;
// Declare the dynamic allocation hooks.
static ACE_Time_Value gettimeofday (const ACE_OS::ACE_HRTimer_Op =
ACE_OS::ACE_HRTIMER_GETTIME);
// THIS FUNCTION IS DEPRECATED. PLEASE USE ACE_OS::gettimeofday ()
// INSTEAD!
// Calls ACE_High_Res_Timer::hrtime_to_tv passing ACE_OS::gethrtime.
// This function can be used to parameterize objects such as
// ACE_Timer_Queue::gettimeofday. If global_scale_factor_ is not
// set, and we're on a platform that requires global_scale_factor_
// (e.g., Win32), ACE_OS::gettimeofday will be used instead of
// ACE_OS::gethrtime. This allows applications on Intel to use
// High_Res_Timer even when global_scale_factor is not set.
// However, setting the global_scale_factor_ appropriately will
// result in the finest resolution possible.
static void hrtime_to_tv (ACE_Time_Value &tv,
const ACE_hrtime_t hrt);
// Converts an <hrt> to <tv> using global_scale_factor_.
private:
static ACE_hrtime_t gettime (const ACE_OS::ACE_HRTimer_Op =
ACE_OS::ACE_HRTIMER_GETTIME);
// For internal use: gets the high-resolution time using
// ACE_OS::gethrtime (). Except on platforms that require
// that the global_scale_factor_ be set, such as ACE_WIN32,
// uses the low-resolution clock if the global_scale_factor_
// has not been set.
ACE_hrtime_t start_;
// Starting time.
ACE_hrtime_t end_;
// Ending time.
ACE_hrtime_t total_;
// Total elapsed time.
ACE_hrtime_t start_incr_;
// Start time of incremental timing.
static ACE_UINT32 global_scale_factor_;
// Converts ticks to microseconds. That is, ticks /
// global_scale_factor_ == microseconds.
static int global_scale_factor_status_;
// Indicates the status of the global scale factor,
// 0 = hasn't been set
// 1 = been set
// -1 = HR timer not supported
};
#if defined (__ACE_INLINE__)
#include "ace/High_Res_Timer.i"
#endif /* __ACE_INLINE__ */
#endif /* ACE_HIGH_RES_TIMER_H */
|
