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/* * PipeTest by Davide Libenzi ( Epoll performace tester ) * Copyright (C) 1999,..,2003 Davide Libenzi * * 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; either version 2 of the License, or * (at your option) any later version. * * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * Davide Libenzi davidel@xmailserver.org * * * You need either a never glibc or the epoll library available here : * * http://www.xmailserver.org/linux-patches/nio-improve.html#sys\_epoll * * to build this source file. To build : * * gcc -o pipetest pipetest.c -lepoll * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #define RUNTIMES 16 static int count, writes, fired; static int *pipes; static int num_pipes, num_active, num_writes; static int epfd; static struct epoll_event *events; unsigned long long getustime(void) { struct timeval tm; gettimeofday(&tm, NULL); return (unsigned long long) tm.tv_sec * 1000000ULL + (unsigned long long) tm.tv_usec; } void read_cb(int fd, int idx) { int widx = idx + num_active + 1; u_char ch; if (read(fd, &ch, sizeof(ch))) count++; else fprintf(stderr, "false read event: fd=%d idx=%d\n", fd, idx); if (writes) { if (widx >= num_pipes) widx -= num_pipes; write(pipes[2 * widx + 1], "e", 1); writes--; fired++; } } int run_once(long *work, unsigned long long *tr) { int i, res; unsigned long long ts, te; fired = 0; for (i = 0; i < num_active; i++, fired++) write(pipes[i * 2 + 1], "e", 1); count = 0; writes = num_writes; ts = getustime(); do { res = epoll_wait(epfd, events, num_pipes, 0); for (i = 0; i < res; i++) read_cb(pipes[2 * events[i].data.u32], events[i].data.u32); } while (count != fired); te = getustime(); *tr = te - ts; *work = count; return (0); } int main (int argc, char **argv) { struct rlimit rl; int i, c; long work; unsigned long long tr; int *cp; struct epoll_event ev; extern char *optarg; num_pipes = 100; num_active = 1; num_writes = num_pipes; while ((c = getopt(argc, argv, "n:a:w:")) != -1) { switch (c) { case 'n': num_pipes = atoi(optarg); break; case 'a': num_active = atoi(optarg); break; case 'w': num_writes = atoi(optarg); break; default: fprintf(stderr, "Illegal argument \"%c\"\n", c); exit(1); } } rl.rlim_cur = rl.rlim_max = num_pipes * 2 + 50; if (setrlimit(RLIMIT_NOFILE, &rl) == -1) { perror("setrlimit"); exit(1); } events = calloc(num_pipes, sizeof(struct epoll_event)); pipes = calloc(num_pipes * 2, sizeof(int)); if (events == NULL || pipes == NULL) { perror("malloc"); exit(1); } if ((epfd = epoll_create(num_pipes)) == -1) { perror("epoll_create"); exit(1); } for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) { if (pipe(cp) == -1) { perror("pipe"); exit(1); } fcntl(cp[0], F_SETFL, fcntl(cp[0], F_GETFL) | O_NONBLOCK); } for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) { ev.events = EPOLLIN; ev.data.u32 = i; if (epoll_ctl(epfd, EPOLL_CTL_ADD, cp[0], &ev) < 0) { perror("epoll_ctl"); exit(1); } } for (i = 0; i < RUNTIMES; i++) { run_once(&work, &tr); if (!work) exit(1); fprintf(stdout, "%lf\n", (double) tr / (double) work); } exit(0); }/davidel@xmailserver.org