diff options
Diffstat (limited to 'ev.pod')
| -rw-r--r-- | ev.pod | 45 |
1 files changed, 45 insertions, 0 deletions
@@ -117,6 +117,12 @@ Returns the current time as libev would use it. Please note that the C<ev_now> function is usually faster and also often returns the timestamp you actually want to know. +=item ev_sleep (ev_tstamp interval) + +Sleep for the given interval: The current thread will be blocked until +either it is interrupted or the given time interval has passed. Basically +this is a subsecond-resolution C<sleep ()>. + =item int ev_version_major () =item int ev_version_minor () @@ -571,6 +577,40 @@ Example: For some weird reason, unregister the above signal handler again. ev_ref (loop); ev_signal_stop (loop, &exitsig); +=item ev_set_io_collect_interval (loop, ev_tstamp interval) + +=item ev_set_timeout_collect_interval (loop, ev_tstamp interval) + +These advanced functions influence the time that libev will spend waiting +for events. Both are by default C<0>, meaning that libev will try to +invoke timer/periodic callbacks and I/O callbacks with minimum latency. + +Setting these to a higher value (the C<interval> I<must> be >= C<0>) +allows libev to delay invocation of I/O and timer/periodic callbacks to +increase efficiency of loop iterations. + +The background is that sometimes your program runs just fast enough to +handle one (or very few) event(s) per loop iteration. While this makes +the program responsive, it also wastes a lot of CPU time to poll for new +events, especially with backends like C<select ()> which have a high +overhead for the actual polling but can deliver many events at once. + +By setting a higher I<io collect interval> you allow libev to spend more +time collecting I/O events, so you can handle more events per iteration, +at the cost of increasing latency. Timeouts (both C<ev_periodic> and +C<ev_timer>) will be not affected. + +Likewise, by setting a higher I<timeout collect interval> you allow libev +to spend more time collecting timeouts, at the expense of increased +latency (the watcher callback will be called later). C<ev_io> watchers +will not be affected. + +Many programs can usually benefit by setting the io collect interval to +a value near C<0.1> or so, which is often enough for interactive servers +(of course not for games), likewise for timeouts. It usually doesn't make +much sense to set it to a lower value than C<0.01>, as this approsaches +the timing granularity of most systems. + =back @@ -2299,6 +2339,11 @@ be attempted. This effectively replaces C<gettimeofday> by C<clock_get (CLOCK_REALTIME, ...)> and will not normally affect correctness. See the note about libraries in the description of C<EV_USE_MONOTONIC>, though. +=item EV_USE_NANOSLEEP + +If defined to be C<1>, libev will assume that C<nanosleep ()> is available +and will use it for delays. Otherwise it will use C<select ()>. + =item EV_USE_SELECT If undefined or defined to be C<1>, libev will compile in support for the |