/*
* Copyright 2003 Niels Provos <provos@citi.umich.edu>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*
* Mon 03/10/2003 - Modified by Davide Libenzi <davidel@xmailserver.org>
*
* Added chain event propagation to improve the sensitivity of
* the measure respect to the event loop efficency.
*
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#ifdef WIN32
#include <windows.h>
#else
#include <sys/socket.h>
#include <signal.h>
#include <sys/resource.h>
#endif
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <event.h>
#include <evutil.h>
static int count, writes, fired;
static int *pipes;
static int num_pipes, num_active, num_writes;
static struct event *events;
static void
read_cb(int fd, short which, void *arg)
{
long idx = (long) arg, widx = idx + 1;
u_char ch;
count += read(fd, &ch, sizeof(ch));
if (writes) {
if (widx >= num_pipes)
widx -= num_pipes;
write(pipes[2 * widx + 1], "e", 1);
writes--;
fired++;
}
}
static struct timeval *
run_once(void)
{
int *cp, space;
long i;
static struct timeval ts, te;
for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
event_del(&events[i]);
event_set(&events[i], cp[0], EV_READ | EV_PERSIST, read_cb, (void *) i);
event_add(&events[i], NULL);
}
event_loop(EVLOOP_ONCE | EVLOOP_NONBLOCK);
fired = 0;
space = num_pipes / num_active;
space = space * 2;
for (i = 0; i < num_active; i++, fired++)
write(pipes[i * space + 1], "e", 1);
count = 0;
writes = num_writes;
{ int xcount = 0;
gettimeofday(&ts, NULL);
do {
event_loop(EVLOOP_ONCE | EVLOOP_NONBLOCK);
xcount++;
} while (count != fired);
gettimeofday(&te, NULL);
if (xcount != count) fprintf(stderr, "Xcount: %d, Rcount: %d\n", xcount, count);
}
evutil_timersub(&te, &ts, &te);
return (&te);
}
int
main (int argc, char **argv)
{
#ifndef WIN32
struct rlimit rl;
#endif
int i, c;
struct timeval *tv;
int *cp;
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);
}
}
#ifndef WIN32
rl.rlim_cur = rl.rlim_max = num_pipes * 2 + 50;
if (setrlimit(RLIMIT_NOFILE, &rl) == -1) {
perror("setrlimit");
exit(1);
}
#endif
events = calloc(num_pipes, sizeof(struct event));
pipes = calloc(num_pipes * 2, sizeof(int));
if (events == NULL || pipes == NULL) {
perror("malloc");
exit(1);
}
event_init();
for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
#ifdef USE_PIPES
if (pipe(cp) == -1) {
#else
if (evutil_socketpair(AF_UNIX, SOCK_STREAM, 0, cp) == -1) {
#endif
perror("pipe");
exit(1);
}
}
for (i = 0; i < 25; i++) {
tv = run_once();
if (tv == NULL)
exit(1);
fprintf(stdout, "%ld\n",
tv->tv_sec * 1000000L + tv->tv_usec);
}
exit(0);
}