On 13/03/2015 15:46, Jason Baron wrote: > > The throttling algorithm computes a duration for the next IO, which is used > > to > > arm a timer in order to delay the request a bit. As timers are always > > rounded > > *UP* to the effective granularity, the timeout being 1ms in epoll_pwait is > > just > > too coarse and will lead to severe inaccuracy. With epoll_pwait1, we can > > avoid > > the rounding-up. > > right, but we could use the timerfd here to get the desired precision.
Fam, didn't you see slowdowns with few file descriptors epoll_ctl+epoll_wait+timerfd compared to ppoll? Do they disappear or improve with epoll_ctl_batch and epoll_pwait1? Paolo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
