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SubjectRe: [Q]: Linux and real device drivers
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>>>>> "Steve" == Steve Underwood <steveu@infowebtelecom.com> writes:

Steve> A much shorter timer works well with this scheme, as it is
Steve> restarted every time something significant happens. Even under
Steve> flood conditions it can't keep restarting forever, as you will
Steve> hit high tide (which is exactly what you want to do). This can
Steve> be implemented with a shorter timer, causing less low traffic
Steve> latency. Under low traffic conditions you may get somewhat more
Steve> interrupts, but under those conditions who cares? This is
Steve> exactly what a 16550A UART does. There, the timer is actually 2
Steve> characters times of idling on the receive line (assuming all
Steve> the clones follow the original NS chip faithfully).

Ok I see what you mean, having an inbetween packet timer might be a
good idea as well.

Steve> I'm not sure why anyone would implement the first strategy. The
Steve> second strategy is just as easy to implement in silicon, but
Steve> will perform better in almost every case. The first strategy
Steve> offers little over using a timed poll. The second strategy
Steve> tunes things more closely to the traffic.

Maybe they didn't think of it.

Jes

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