Messages in this thread | | | Subject | Re: [Q]: Linux and real device drivers | From | Jes Sorensen <> | Date | 23 Sep 1999 11:38:28 +0200 |
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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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