Re: Task queue makes slow device even slower

David Woodhouse (David.Woodhouse@mvhi.com)
Wed, 27 Oct 1999 18:34:37 +0100

alan@lxorguk.ukuu.org.uk said:
> You are constrained by timer resolution. Do you have a spare timer
> and irq you can rig for this. If not the best you can do is probably
> to use tq_immed and at least the udelays will not impact irq latency

It's often been suggested, and it's a long way down my TODO list, that we
should have the facility to shift the kernel timer tick onto the RTC, thereby
leaving the 8254 timer available for this kind of thing.

(We can't use the RTC because its range of frequencies is too restricted. It's
fine for timer ticks, though.)

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