示例#1
0
int test(){


#ifdef _OSD_POSIX
    if ((pid = os_fork(ap_unixd_config.user_name)) == -1) {
#else
    if ((pid = fork()) == -1) {
#endif
        // code
    }


}
示例#2
0
static int make_child(server_rec *s, int slot)
{
    int pid;

    if (slot + 1 > ap_max_daemons_limit) {
	ap_max_daemons_limit = slot + 1;
    }

    if (one_process) {
	apr_signal(SIGHUP, just_die);
        /* Don't catch AP_SIG_GRACEFUL in ONE_PROCESS mode :) */
	apr_signal(SIGINT, just_die);
#ifdef SIGQUIT
	apr_signal(SIGQUIT, SIG_DFL);
#endif
	apr_signal(SIGTERM, just_die);
	child_main(slot);
    }

    (void) ap_update_child_status_from_indexes(slot, 0, SERVER_STARTING,
                                               (request_rec *) NULL);


#ifdef _OSD_POSIX
    /* BS2000 requires a "special" version of fork() before a setuid() call */
    if ((pid = os_fork(unixd_config.user_name)) == -1) {
#elif defined(TPF)
    if ((pid = os_fork(s, slot)) == -1) {
#else
    if ((pid = fork()) == -1) {
#endif
	ap_log_error(APLOG_MARK, APLOG_ERR, errno, s, "fork: Unable to fork new process");

	/* fork didn't succeed. Fix the scoreboard or else
	 * it will say SERVER_STARTING forever and ever
	 */
	(void) ap_update_child_status_from_indexes(slot, 0, SERVER_DEAD,
                                                   (request_rec *) NULL);

	/* In case system resources are maxxed out, we don't want
	   Apache running away with the CPU trying to fork over and
	   over and over again. */
	sleep(10);

	return -1;
    }

    if (!pid) {
#ifdef HAVE_BINDPROCESSOR
        /* by default AIX binds to a single processor
         * this bit unbinds children which will then bind to another cpu
         */
	int status = bindprocessor(BINDPROCESS, (int)getpid(), 
				   PROCESSOR_CLASS_ANY);
	if (status != OK) {
	    ap_log_error(APLOG_MARK, APLOG_WARNING, errno, 
                         ap_server_conf, "processor unbind failed %d", status);
	}
#endif
	RAISE_SIGSTOP(MAKE_CHILD);
        AP_MONCONTROL(1);
        /* Disable the parent's signal handlers and set up proper handling in
         * the child.
	 */
	apr_signal(SIGHUP, just_die);
	apr_signal(SIGTERM, just_die);
        /* The child process doesn't do anything for AP_SIG_GRACEFUL.  
         * Instead, the pod is used for signalling graceful restart.
         */
        apr_signal(AP_SIG_GRACEFUL, SIG_IGN);
	child_main(slot);
    }

    ap_scoreboard_image->parent[slot].pid = pid;

    return 0;
}


/* start up a bunch of children */
static void startup_children(int number_to_start)
{
    int i;

    for (i = 0; number_to_start && i < ap_daemons_limit; ++i) {
	if (ap_scoreboard_image->servers[i][0].status != SERVER_DEAD) {
	    continue;
	}
	if (make_child(ap_server_conf, i) < 0) {
	    break;
	}
	--number_to_start;
    }
}


/*
 * idle_spawn_rate is the number of children that will be spawned on the
 * next maintenance cycle if there aren't enough idle servers.  It is
 * doubled up to MAX_SPAWN_RATE, and reset only when a cycle goes by
 * without the need to spawn.
 */
static int idle_spawn_rate = 1;
#ifndef MAX_SPAWN_RATE
#define MAX_SPAWN_RATE	(32)
#endif
static int hold_off_on_exponential_spawning;

static void perform_idle_server_maintenance(apr_pool_t *p)
{
    int i;
    int to_kill;
    int idle_count;
    worker_score *ws;
    int free_length;
    int free_slots[MAX_SPAWN_RATE];
    int last_non_dead;
    int total_non_dead;

    /* initialize the free_list */
    free_length = 0;

    to_kill = -1;
    idle_count = 0;
    last_non_dead = -1;
    total_non_dead = 0;

    for (i = 0; i < ap_daemons_limit; ++i) {
	int status;

	if (i >= ap_max_daemons_limit && free_length == idle_spawn_rate)
	    break;
	ws = &ap_scoreboard_image->servers[i][0];
	status = ws->status;
	if (status == SERVER_DEAD) {
	    /* try to keep children numbers as low as possible */
	    if (free_length < idle_spawn_rate) {
		free_slots[free_length] = i;
		++free_length;
	    }
	}
	else {
	    /* We consider a starting server as idle because we started it
	     * at least a cycle ago, and if it still hasn't finished starting
	     * then we're just going to swamp things worse by forking more.
	     * So we hopefully won't need to fork more if we count it.
	     * This depends on the ordering of SERVER_READY and SERVER_STARTING.
	     */
	    if (status <= SERVER_READY) {
		++ idle_count;
		/* always kill the highest numbered child if we have to...
		 * no really well thought out reason ... other than observing
		 * the server behaviour under linux where lower numbered children
		 * tend to service more hits (and hence are more likely to have
		 * their data in cpu caches).
		 */
		to_kill = i;
	    }

	    ++total_non_dead;
	    last_non_dead = i;
	}
    }
    ap_max_daemons_limit = last_non_dead + 1;
    if (idle_count > ap_daemons_max_free) {
	/* kill off one child... we use the pod because that'll cause it to
	 * shut down gracefully, in case it happened to pick up a request
	 * while we were counting
	 */
	ap_mpm_pod_signal(pod);
	idle_spawn_rate = 1;
    }
    else if (idle_count < ap_daemons_min_free) {
	/* terminate the free list */
	if (free_length == 0) {
	    /* only report this condition once */
	    static int reported = 0;

	    if (!reported) {
		ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf,
			    "server reached MaxClients setting, consider"
			    " raising the MaxClients setting");
		reported = 1;
	    }
	    idle_spawn_rate = 1;
	}
	else {
	    if (idle_spawn_rate >= 8) {
		ap_log_error(APLOG_MARK, APLOG_INFO, 0, ap_server_conf,
		    "server seems busy, (you may need "
		    "to increase StartServers, or Min/MaxSpareServers), "
		    "spawning %d children, there are %d idle, and "
		    "%d total children", idle_spawn_rate,
		    idle_count, total_non_dead);
	    }
	    for (i = 0; i < free_length; ++i) {
#ifdef TPF
        if (make_child(ap_server_conf, free_slots[i]) == -1) {
            if(free_length == 1) {
                shutdown_pending = 1;
                ap_log_error(APLOG_MARK, APLOG_EMERG, 0, ap_server_conf,
                "No active child processes: shutting down");
            }
        }
#else
		make_child(ap_server_conf, free_slots[i]);
#endif /* TPF */
	    }
	    /* the next time around we want to spawn twice as many if this
	     * wasn't good enough, but not if we've just done a graceful
	     */
	    if (hold_off_on_exponential_spawning) {
		--hold_off_on_exponential_spawning;
	    }
	    else if (idle_spawn_rate < MAX_SPAWN_RATE) {
		idle_spawn_rate *= 2;
	    }
	}
    }
    else {
	idle_spawn_rate = 1;
    }
}