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
|
/*
* Mach Operating System
* Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
* File: kern/mach_factor.c
* Author: Avadis Tevanian, Jr.
* Date: 1986
*
* Compute the Mach Factor.
*/
#include <mach/machine.h>
#include <mach/processor_info.h>
#include <kern/sched.h>
#include <kern/processor.h>
#include <kern/time_out.h>
#if MACH_KERNEL
#include <mach/kern_return.h>
#include <mach/port.h>
#endif /* MACH_KERNEL */
#include "mach_factor.h"
long avenrun[3] = {0, 0, 0};
long mach_factor[3] = {0, 0, 0};
/*
* Values are scaled by LOAD_SCALE, defined in processor_info.h
*/
static long fract[3] = {
800, /* (4.0/5.0) 5 second average */
966, /* (29.0/30.0) 30 second average */
983, /* (59.0/60.) 1 minute average */
};
void compute_mach_factor()
{
register processor_set_t pset;
register processor_t processor;
register int ncpus;
register int nthreads;
register long factor_now;
register long average_now;
register long load_now;
simple_lock(&all_psets_lock);
pset = (processor_set_t) queue_first(&all_psets);
while (!queue_end(&all_psets, (queue_entry_t)pset)) {
/*
* If no processors, this pset is in suspended animation.
* No load calculations are performed.
*/
pset_lock(pset);
if((ncpus = pset->processor_count) > 0) {
/*
* Count number of threads.
*/
nthreads = pset->runq.count;
processor = (processor_t) queue_first(&pset->processors);
while (!queue_end(&pset->processors,
(queue_entry_t)processor)) {
nthreads += processor->runq.count;
processor =
(processor_t) queue_next(&processor->processors);
}
/*
* account for threads on cpus.
*/
nthreads += ncpus - pset->idle_count;
/*
* The current thread (running this calculation)
* doesn't count; it's always in the default pset.
*/
if (pset == &default_pset)
nthreads -= 1;
if (nthreads > ncpus) {
factor_now = (ncpus * LOAD_SCALE) / (nthreads + 1);
load_now = (nthreads << SCHED_SHIFT) / ncpus;
}
else {
factor_now = (ncpus - nthreads) * LOAD_SCALE;
load_now = SCHED_SCALE;
}
/*
* Load average and mach factor calculations for
* those that ask about these things.
*/
average_now = nthreads * LOAD_SCALE;
pset->mach_factor =
((pset->mach_factor << 2) + factor_now)/5;
pset->load_average =
((pset->load_average << 2) + average_now)/5;
/*
* And some ugly stuff to keep w happy.
*/
if (pset == &default_pset) {
register int i;
for (i = 0; i < 3; i++) {
mach_factor[i] = ( (mach_factor[i]*fract[i])
+ (factor_now*(LOAD_SCALE-fract[i])) )
/ LOAD_SCALE;
avenrun[i] = ( (avenrun[i]*fract[i])
+ (average_now*(LOAD_SCALE-fract[i])) )
/ LOAD_SCALE;
}
}
/*
* sched_load is the only thing used by scheduler.
* It is always at least 1 (i.e. SCHED_SCALE).
*/
pset->sched_load = (pset->sched_load + load_now) >> 1;
}
pset_unlock(pset);
pset = (processor_set_t) queue_next(&pset->all_psets);
}
simple_unlock(&all_psets_lock);
}
|
