On Fri, Oct 18, 2002 at 12:29:14PM +0300, Momchil Velikov wrote:
> >>>>> "Jan" == Jan Hudec <bulb@ucw.cz> writes:
>
> Jan> On Thu, Oct 17, 2002 at 03:39:21PM +0300, Momchil Velikov wrote:
> Nagaraj> for( buff_index = i = 0; i < xfer_count; i++, buff_index =
> Nagaraj> (buff_index+1)%MAX_BUFFERS ) {
> >>
> Nagaraj> sleep(1000);
> >>
> Nagaraj> read( buff_fd, (mbuff +buff_index*BUFF_SIZE), BUFF_SIZE );
> >>
> Nagaraj> }
> >>
> >> First, the above code has a race condition, which can add up to 1000 sec (!)
> >> latency per frame!
>
> Jan> Yes, there is. But first, it skips only to the next frame and
>
> I wouldn't call 1000 seconds "only".
>
> But, yes, not per frame, but per xfer_count frames.
No. You still don't seem to realize, that a signal is emited each time
one buffer is completed. And as the buffer is at most one frame, signals
are sent at least at frame rate. That is some 1/18 or 1/25 second period
or something like that. And that is actually the upper bound for time
the sleep can sleep. I hope I have the right to call 1/18 second "only".
-------------------------------------------------------------------------------
Jan 'Bulb' Hudec <bulb@ucw.cz>
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