1 /* Benchmark malloc and free functions.
2 Copyright (C) 2013-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #include <errno.h>
20 #include <math.h>
21 #include <pthread.h>
22 #include <signal.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <sys/time.h>
27 #include <sys/resource.h>
28 #include <unistd.h>
29
30 #include "bench-timing.h"
31 #include "json-lib.h"
32
33 /* Benchmark duration in seconds. */
34 #define BENCHMARK_DURATION 10
35 #define RAND_SEED 88
36
37 #ifndef NUM_THREADS
38 # define NUM_THREADS 1
39 #endif
40
41 /* Maximum memory that can be allocated at any one time is:
42
43 NUM_THREADS * WORKING_SET_SIZE * MAX_ALLOCATION_SIZE
44
45 However due to the distribution of the random block sizes
46 the typical amount allocated will be much smaller. */
47 #define WORKING_SET_SIZE 1024
48
49 #define MIN_ALLOCATION_SIZE 4
50 #define MAX_ALLOCATION_SIZE 32768
51
52 /* Get a random block size with an inverse square distribution. */
53 static unsigned int
54 get_block_size (unsigned int rand_data)
55 {
56 /* Inverse square. */
57 const float exponent = -2;
58 /* Minimum value of distribution. */
59 const float dist_min = MIN_ALLOCATION_SIZE;
60 /* Maximum value of distribution. */
61 const float dist_max = MAX_ALLOCATION_SIZE;
62
63 float min_pow = powf (dist_min, exponent + 1);
64 float max_pow = powf (dist_max, exponent + 1);
65
66 float r = (float) rand_data / RAND_MAX;
67
68 return (unsigned int) powf ((max_pow - min_pow) * r + min_pow,
69 1 / (exponent + 1));
70 }
71
72 #define NUM_BLOCK_SIZES 8000
73 #define NUM_OFFSETS ((WORKING_SET_SIZE) * 4)
74
75 static unsigned int random_block_sizes[NUM_BLOCK_SIZES];
76 static unsigned int random_offsets[NUM_OFFSETS];
77
78 static void
79 init_random_values (void)
80 {
81 for (size_t i = 0; i < NUM_BLOCK_SIZES; i++)
82 random_block_sizes[i] = get_block_size (rand ());
83
84 for (size_t i = 0; i < NUM_OFFSETS; i++)
85 random_offsets[i] = rand () % WORKING_SET_SIZE;
86 }
87
88 static unsigned int
89 get_random_block_size (unsigned int *state)
90 {
91 unsigned int idx = *state;
92
93 if (idx >= NUM_BLOCK_SIZES - 1)
94 idx = 0;
95 else
96 idx++;
97
98 *state = idx;
99
100 return random_block_sizes[idx];
101 }
102
103 static unsigned int
104 get_random_offset (unsigned int *state)
105 {
106 unsigned int idx = *state;
107
108 if (idx >= NUM_OFFSETS - 1)
109 idx = 0;
110 else
111 idx++;
112
113 *state = idx;
114
115 return random_offsets[idx];
116 }
117
118 static volatile bool timeout;
119
120 static void
121 alarm_handler (int signum)
122 {
123 timeout = true;
124 }
125
126 /* Allocate and free blocks in a random order. */
127 static size_t
128 malloc_benchmark_loop (void **ptr_arr)
129 {
130 unsigned int offset_state = 0, block_state = 0;
131 size_t iters = 0;
132
133 while (!timeout)
134 {
135 unsigned int next_idx = get_random_offset (&offset_state);
136 unsigned int next_block = get_random_block_size (&block_state);
137
138 free (ptr_arr[next_idx]);
139
140 ptr_arr[next_idx] = malloc (next_block);
141
142 iters++;
143 }
144
145 return iters;
146 }
147
148 struct thread_args
149 {
150 size_t iters;
151 void **working_set;
152 timing_t elapsed;
153 };
154
155 static void *
156 benchmark_thread (void *arg)
157 {
158 struct thread_args *args = (struct thread_args *) arg;
159 size_t iters;
160 void *thread_set = args->working_set;
161 timing_t start, stop;
162
163 TIMING_NOW (start);
164 iters = malloc_benchmark_loop (thread_set);
165 TIMING_NOW (stop);
166
167 TIMING_DIFF (args->elapsed, start, stop);
168 args->iters = iters;
169
170 return NULL;
171 }
172
173 static timing_t
174 do_benchmark (size_t num_threads, size_t *iters)
175 {
176 timing_t elapsed = 0;
177
178 if (num_threads == 1)
179 {
180 timing_t start, stop;
181 void *working_set[WORKING_SET_SIZE];
182
183 memset (working_set, 0, sizeof (working_set));
184
185 TIMING_NOW (start);
186 *iters = malloc_benchmark_loop (working_set);
187 TIMING_NOW (stop);
188
189 TIMING_DIFF (elapsed, start, stop);
190 }
191 else
192 {
193 struct thread_args args[num_threads];
194 void *working_set[num_threads][WORKING_SET_SIZE];
195 pthread_t threads[num_threads];
196
197 memset (working_set, 0, sizeof (working_set));
198
199 *iters = 0;
200
201 for (size_t i = 0; i < num_threads; i++)
202 {
203 args[i].working_set = working_set[i];
204 pthread_create(&threads[i], NULL, benchmark_thread, &args[i]);
205 }
206
207 for (size_t i = 0; i < num_threads; i++)
208 {
209 pthread_join(threads[i], NULL);
210 TIMING_ACCUM (elapsed, args[i].elapsed);
211 *iters += args[i].iters;
212 }
213 }
214 return elapsed;
215 }
216
217 static void usage(const char *name)
218 {
219 fprintf (stderr, "%s: <num_threads>\n", name);
220 exit (1);
221 }
222
223 int
224 main (int argc, char **argv)
225 {
226 timing_t cur;
227 size_t iters = 0, num_threads = 1;
228 json_ctx_t json_ctx;
229 double d_total_s, d_total_i;
230 struct sigaction act;
231
232 if (argc == 1)
233 num_threads = 1;
234 else if (argc == 2)
235 {
236 long ret;
237
238 errno = 0;
239 ret = strtol(argv[1], NULL, 10);
240
241 if (errno || ret == 0)
242 usage(argv[0]);
243
244 num_threads = ret;
245 }
246 else
247 usage(argv[0]);
248
249 init_random_values ();
250
251 json_init (&json_ctx, 0, stdout);
252
253 json_document_begin (&json_ctx);
254
255 json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
256
257 json_attr_object_begin (&json_ctx, "functions");
258
259 json_attr_object_begin (&json_ctx, "malloc");
260
261 json_attr_object_begin (&json_ctx, "");
262
263 memset (&act, 0, sizeof (act));
264 act.sa_handler = &alarm_handler;
265
266 sigaction (SIGALRM, &act, NULL);
267
268 alarm (BENCHMARK_DURATION);
269
270 cur = do_benchmark (num_threads, &iters);
271
272 struct rusage usage;
273 getrusage(RUSAGE_SELF, &usage);
274
275 d_total_s = cur;
276 d_total_i = iters;
277
278 json_attr_double (&json_ctx, "duration", d_total_s);
279 json_attr_double (&json_ctx, "iterations", d_total_i);
280 json_attr_double (&json_ctx, "time_per_iteration", d_total_s / d_total_i);
281 json_attr_double (&json_ctx, "max_rss", usage.ru_maxrss);
282
283 json_attr_double (&json_ctx, "threads", num_threads);
284 json_attr_double (&json_ctx, "min_size", MIN_ALLOCATION_SIZE);
285 json_attr_double (&json_ctx, "max_size", MAX_ALLOCATION_SIZE);
286 json_attr_double (&json_ctx, "random_seed", RAND_SEED);
287
288 json_attr_object_end (&json_ctx);
289
290 json_attr_object_end (&json_ctx);
291
292 json_attr_object_end (&json_ctx);
293
294 json_document_end (&json_ctx);
295
296 return 0;
297 }