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
222
223
224
225
226
227
228
229
230
231
|
/* Copyright (c) 2004, 2011, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA */
/* get time since epoc in 100 nanosec units */
/* thus to get the current time we should use the system function
with the highest possible resolution */
/*
TODO: in functions my_micro_time() and my_micro_time_and_time() there
exists some common code that should be merged into a function.
*/
#include "mysys_priv.h"
#include "my_static.h"
#ifdef __NETWARE__
#include <nks/time.h>
#endif
ulonglong my_getsystime()
{
#ifdef HAVE_CLOCK_GETTIME
struct timespec tp;
clock_gettime(CLOCK_REALTIME, &tp);
return (ulonglong)tp.tv_sec*10000000+(ulonglong)tp.tv_nsec/100;
#elif defined(__WIN__)
LARGE_INTEGER t_cnt;
if (query_performance_frequency)
{
QueryPerformanceCounter(&t_cnt);
return ((t_cnt.QuadPart / query_performance_frequency * 10000000) +
((t_cnt.QuadPart % query_performance_frequency) * 10000000 /
query_performance_frequency) + query_performance_offset);
}
return 0;
#elif defined(__NETWARE__)
NXTime_t tm;
NXGetTime(NX_SINCE_1970, NX_NSECONDS, &tm);
return (ulonglong)tm/100;
#else
/* TODO: check for other possibilities for hi-res timestamping */
struct timeval tv;
gettimeofday(&tv,NULL);
return (ulonglong)tv.tv_sec*10000000+(ulonglong)tv.tv_usec*10;
#endif
}
/*
Return current time
SYNOPSIS
my_time()
flags If MY_WME is set, write error if time call fails
*/
time_t my_time(myf flags __attribute__((unused)))
{
time_t t;
#ifdef HAVE_GETHRTIME
(void) my_micro_time_and_time(&t);
return t;
#else
/* The following loop is here beacuse time() may fail on some systems */
while ((t= time(0)) == (time_t) -1)
{
if (flags & MY_WME)
fprintf(stderr, "%s: Warning: time() call failed\n", my_progname);
}
return t;
#endif
}
/*
Return time in micro seconds
SYNOPSIS
my_micro_time()
NOTES
This function is to be used to measure performance in micro seconds.
As it's not defined whats the start time for the clock, this function
us only useful to measure time between two moments.
For windows platforms we need the frequency value of the CUP. This is
initalized in my_init.c through QueryPerformanceFrequency().
If Windows platform doesn't support QueryPerformanceFrequency() we will
obtain the time via GetClockCount, which only supports milliseconds.
RETURN
Value in microseconds from some undefined point in time
*/
ulonglong my_micro_time()
{
#if defined(__WIN__)
ulonglong newtime;
GetSystemTimeAsFileTime((FILETIME*)&newtime);
return (newtime/10);
#elif defined(HAVE_GETHRTIME)
return gethrtime()/1000;
#else
ulonglong newtime;
struct timeval t;
/*
The following loop is here because gettimeofday may fail on some systems
*/
while (gettimeofday(&t, NULL) != 0)
{}
newtime= (ulonglong)t.tv_sec * 1000000 + t.tv_usec;
return newtime;
#endif /* defined(__WIN__) */
}
/*
Return time in seconds and timer in microseconds (not different start!)
SYNOPSIS
my_micro_time_and_time()
time_arg Will be set to seconds since epoch (00:00:00 UTC,
January 1, 1970)
NOTES
This function is to be useful when we need both the time and microtime.
For example in MySQL this is used to get the query time start of a query
and to measure the time of a query (for the slow query log)
IMPLEMENTATION
Value of time is as in time() call.
Value of microtime is same as my_micro_time(), which may be totally
unrealated to time()
RETURN
Value in microseconds from some undefined point in time
*/
#define DELTA_FOR_SECONDS LL(500000000) /* Half a second */
ulonglong my_micro_time_and_time(time_t *time_arg)
{
#if defined(__WIN__)
ulonglong newtime;
GetSystemTimeAsFileTime((FILETIME*)&newtime);
*time_arg= (time_t) ((newtime - OFFSET_TO_EPOCH) / 10000000);
return (newtime/10);
#elif defined(HAVE_GETHRTIME)
/*
Solaris has a very slow time() call. We optimize this by using the very
fast gethrtime() call and only calling time() every 1/2 second
*/
static hrtime_t prev_gethrtime= 0;
static time_t cur_time= 0;
hrtime_t cur_gethrtime;
pthread_mutex_lock(&THR_LOCK_time);
cur_gethrtime= gethrtime();
/*
Due to bugs in the Solaris (x86) implementation of gethrtime(),
the time returned by it might not be monotonic. Don't use the
cached time(2) value if this is a case.
*/
if ((prev_gethrtime > cur_gethrtime) ||
((cur_gethrtime - prev_gethrtime) > DELTA_FOR_SECONDS))
{
cur_time= time(0);
prev_gethrtime= cur_gethrtime;
}
*time_arg= cur_time;
pthread_mutex_unlock(&THR_LOCK_time);
return cur_gethrtime/1000;
#else
ulonglong newtime;
struct timeval t;
/*
The following loop is here because gettimeofday may fail on some systems
*/
while (gettimeofday(&t, NULL) != 0)
{}
*time_arg= t.tv_sec;
newtime= (ulonglong)t.tv_sec * 1000000 + t.tv_usec;
return newtime;
#endif /* defined(__WIN__) */
}
/*
Returns current time
SYNOPSIS
my_time_possible_from_micro()
microtime Value from very recent my_micro_time()
NOTES
This function returns the current time. The microtime argument is only used
if my_micro_time() uses a function that can safely be converted to the
current time.
RETURN
current time
*/
time_t my_time_possible_from_micro(ulonglong microtime __attribute__((unused)))
{
#if defined(__WIN__)
time_t t;
while ((t= time(0)) == (time_t) -1)
{}
return t;
#elif defined(HAVE_GETHRTIME)
return my_time(0); /* Cached time */
#else
return (time_t) (microtime / 1000000);
#endif /* defined(__WIN__) */
}
|
