void
VTIM_sleep(double t)
{
#ifdef HAVE_NANOSLEEP
struct timespec ts;
ts = VTIM_timespec(t);
(void)nanosleep(&ts, NULL);
#else
if (t >= 1.) {
(void)sleep(floor(t));
t -= floor(t);
}
/* XXX: usleep() is not mandated to be thread safe */
t *= 1e6;
if (t > 0)
(void)usleep(floor(t));
#endif
}
static void *
vws_thread(void *priv)
{
struct sess *sp;
struct vws *vws;
CAST_OBJ_NOTNULL(vws, priv, VWS_MAGIC);
/*
* timeouts:
*
* min_ts : Minimum timeout for port_getn
* min_t : ^ equivalent in floating point representation
*
* max_ts : Maximum timeout for port_getn
* max_t : ^ equivalent in floating point representation
*
* with (nevents == 1), we should always choose the correct port_getn
* timeout to check session timeouts, so max is just a safety measure
* (if this implementation is correct, it could be set to an "infinte"
* value)
*
* with (nevents > 1), min and max define the acceptable range for
* - additional latency of keep-alive connections and
* - additional tolerance for handling session timeouts
*
*/
static struct timespec min_ts = {0L, 100L /*ms*/ * 1000L /*us*/ * 1000L /*ns*/};
static double min_t = 0.1; /* 100 ms*/
static struct timespec max_ts = {1L, 0L}; /* 1 second */
static double max_t = 1.0; /* 1 second */
/* XXX: These should probably go in vws ? */
struct timespec ts;
struct timespec *timeout;
vws->dport = port_create();
assert(vws->dport >= 0);
timeout = &max_ts;
while (1) {
port_event_t ev[MAX_EVENTS];
int nevents, ei, ret;
double now, deadline;
/*
* XXX Do we want to scale this up dynamically to increase
* efficiency in high throughput situations? - would need to
* start with one to keep latency low at any rate
*
* Note: when increasing nevents, we must lower min_ts
* and max_ts
*/
nevents = 1;
/*
* see disucssion in
* - https://issues.apache.org/bugzilla/show_bug.cgi?id=47645
* - http://mail.opensolaris.org/pipermail/networking-discuss/2009-August/011979.html
*
* comment from apr/poll/unix/port.c :
*
* This confusing API can return an event at the same time
* that it reports EINTR or ETIME.
*
*/
ret = port_getn(vws->dport, ev, MAX_EVENTS, &nevents, timeout);
if (ret < 0)
assert((errno == EINTR) || (errno == ETIME));
for (ei = 0; ei < nevents; ei++)
vws_port_ev(vws, ev + ei);
/* check for timeouts */
now = VTIM_real();
deadline = now - cache_param->sess_timeout;
/*
* This loop assumes that the oldest sessions are always at the
* beginning of the list (which is the case if we guarantee to
* enqueue at the tail only
*
*/
for (;;) {
sp = VTAILQ_FIRST(&vws->sesshead);
if (sp == NULL)
break;
if (sp->t_open > deadline) {
break;
}
VTAILQ_REMOVE(&vws->sesshead, sp, list);
if(sp->fd != -1) {
vws_del(vws, sp->fd);
}
SES_Delete(sp, "timeout");
}
/*
* Calculate the timeout for the next get_portn
*/
if (sp) {
double tmo = (sp->t_open + cache_param->sess_timeout) - now;
/* we should have removed all sps whose timeout has passed */
assert(tmo > 0.0);
if (tmo < min_t) {
timeout = &min_ts;
} else if (tmo > max_t) {
timeout = &max_ts;
} else {
ts = VTIM_timespec(tmo);
timeout = &ts;
}
} else {
timeout = &max_ts;
}
}
}
