diff options
Diffstat (limited to 'ev.pod')
-rw-r--r-- | ev.pod | 18 |
1 files changed, 15 insertions, 3 deletions
@@ -2153,9 +2153,12 @@ Another way to think about it (for the mathematically inclined) is that C<ev_periodic> will try to run the callback in this mode at the next possible time where C<time = offset (mod interval)>, regardless of any time jumps. -For numerical stability it is preferable that the C<offset> value is near -C<ev_now ()> (the current time), but there is no range requirement for -this value, and in fact is often specified as zero. +The C<interval> I<MUST> be positive, and for numerical stability, the +interval value should be higher than C<1/8192> (which is around 100 +microseconds) and C<offset> should be higher than C<0> and should have +at most a similar magnitude as the current time (say, within a factor of +ten). Typical values for offset are, in fact, C<0> or something between +C<0> and C<interval>, which is also the recommended range. Note also that there is an upper limit to how often a timer can fire (CPU speed for example), so if C<interval> is very small then timing stability @@ -4206,6 +4209,15 @@ F<event.h> that are not directly supported by the libev core alone. In standalone mode, libev will still try to automatically deduce the configuration, but has to be more conservative. +=item EV_USE_FLOOR + +If defined to be C<1>, libev will use the C<floor ()> function for its +periodic reschedule calculations, otherwise libev will fall back on a +portable (slower) implementation. If you enable this, you usually have to +link against libm or something equivalent. Enabling this when the C<floor> +function is not available will fail, so the safe default is to not enable +this. + =item EV_USE_MONOTONIC If defined to be C<1>, libev will try to detect the availability of the |