urbit/outside/libuv_0.11/test/benchmark-fs-stat.c
2014-08-22 17:39:21 -04:00

137 lines
4.0 KiB
C

/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include "task.h"
#include "uv.h"
#include <stdio.h>
#include <stdlib.h>
#define NUM_SYNC_REQS (10 * 1e5)
#define NUM_ASYNC_REQS (1 * (int) 1e5)
#define MAX_CONCURRENT_REQS 32
#define sync_stat(req, path) \
do { \
uv_fs_stat(uv_default_loop(), (req), (path), NULL); \
uv_fs_req_cleanup((req)); \
} \
while (0)
struct async_req {
const char* path;
uv_fs_t fs_req;
int* count;
};
static void warmup(const char* path) {
uv_fs_t reqs[MAX_CONCURRENT_REQS];
unsigned int i;
/* warm up the thread pool */
for (i = 0; i < ARRAY_SIZE(reqs); i++)
uv_fs_stat(uv_default_loop(), reqs + i, path, uv_fs_req_cleanup);
uv_run(uv_default_loop(), UV_RUN_DEFAULT);
/* warm up the OS dirent cache */
for (i = 0; i < 16; i++)
sync_stat(reqs + 0, path);
}
static void sync_bench(const char* path) {
uint64_t before;
uint64_t after;
uv_fs_t req;
int i;
/* do the sync benchmark */
before = uv_hrtime();
for (i = 0; i < NUM_SYNC_REQS; i++)
sync_stat(&req, path);
after = uv_hrtime();
printf("%s stats (sync): %.2fs (%s/s)\n",
fmt(1.0 * NUM_SYNC_REQS),
(after - before) / 1e9,
fmt((1.0 * NUM_SYNC_REQS) / ((after - before) / 1e9)));
fflush(stdout);
}
static void stat_cb(uv_fs_t* fs_req) {
struct async_req* req = container_of(fs_req, struct async_req, fs_req);
uv_fs_req_cleanup(&req->fs_req);
if (*req->count == 0) return;
uv_fs_stat(uv_default_loop(), &req->fs_req, req->path, stat_cb);
(*req->count)--;
}
static void async_bench(const char* path) {
struct async_req reqs[MAX_CONCURRENT_REQS];
struct async_req* req;
uint64_t before;
uint64_t after;
int count;
int i;
for (i = 1; i <= MAX_CONCURRENT_REQS; i++) {
count = NUM_ASYNC_REQS;
for (req = reqs; req < reqs + i; req++) {
req->path = path;
req->count = &count;
uv_fs_stat(uv_default_loop(), &req->fs_req, req->path, stat_cb);
}
before = uv_hrtime();
uv_run(uv_default_loop(), UV_RUN_DEFAULT);
after = uv_hrtime();
printf("%s stats (%d concurrent): %.2fs (%s/s)\n",
fmt(1.0 * NUM_ASYNC_REQS),
i,
(after - before) / 1e9,
fmt((1.0 * NUM_ASYNC_REQS) / ((after - before) / 1e9)));
fflush(stdout);
}
}
/* This benchmark aims to measure the overhead of doing I/O syscalls from
* the thread pool. The stat() syscall was chosen because its results are
* easy for the operating system to cache, taking the actual I/O overhead
* out of the equation.
*/
BENCHMARK_IMPL(fs_stat) {
const char path[] = ".";
warmup(path);
sync_bench(path);
async_bench(path);
MAKE_VALGRIND_HAPPY();
return 0;
}