cosmopolitan/tool/viz/malloc_scalability.c
Justine Tunney 0a79c6961f
Make malloc scalable on all platforms
It turns out sched_getcpu() didn't work on many platforms. So the system
call now has tests and is well documented. We now employ new workarounds
on platforms where it isn't supported in our malloc() implementation. It
was previously the case that malloc() was only scalable on Linux/Windows
for x86-64. Now the other platforms are scalable too.
2024-08-15 23:32:53 -07:00

55 lines
2.7 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi │
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2024 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/struct/timespec.h"
#include "libc/mem/mem.h"
#include "libc/runtime/runtime.h"
#include "libc/thread/thread.h"
#define ALLOCATIONS 1000
void *worker(void *arg) {
void **ptrs = malloc(ALLOCATIONS * sizeof(void *));
for (int i = 0; i < ALLOCATIONS; ++i)
ptrs[i] = malloc(1);
for (int i = 0; i < ALLOCATIONS; ++i)
free(ptrs[i]);
free(ptrs);
return 0;
}
void test(int n) {
struct timespec start = timespec_real();
pthread_t *th = malloc(sizeof(pthread_t) * n);
for (int i = 0; i < n; ++i)
pthread_create(th + i, 0, worker, 0);
for (int i = 0; i < n; ++i)
pthread_join(th[i], 0);
free(th);
struct timespec end = timespec_real();
printf("%2d threads * %d allocs = %ld us\n", n, ALLOCATIONS,
timespec_tomicros(timespec_sub(end, start)));
}
int main(int argc, char *argv[]) {
int n = __get_cpu_count();
if (n < 8)
n = 8;
for (int i = 1; i <= n; ++i)
test(i);
}