I tried the 1us -> (1000|10000)us sleep approach first, before using the
ringbuffer timeouts -- saw no noticeable difference wrt performance.
10ms timeouts seemed to be enough (it's the resolution of a HZ==100 kernel)
and gave similar interrupt and cs numbers as w/ low-res timers.

Is this patch for streamdev a direct result from selecting the new "Tickless System (Dynamic Ticks)" option in kernel 2.6.21? If yes, then does the new "dynamic" timer effect vdr's performance as well?

Best Regards.