Re: [2.4.17/18pre] VM and swap - it's really unusable

[Nigel Gamble]

On Thu, 10 Jan 2002, Alan Cox wrote:
> The fun below 1mS comes from
>
> 	1.	APM bios calls where the bios decides to take >1mS to have
> 		a chat with your batteries
> 	2.	Video cards pulling borderline legal PCI tricks to get
> 		better benchmarketing by stalling the entire bus

Don't forget the embedded space, where the hardware vendor can ensure
that their hardware is well-behaved.  Even on a PC, it is possible for
someone who cares about realtime to spec a reasonable system.

On good hardware, we can easily do much better than 1ms latency with a
preemptible kernel and a spinlock cleanup.  I don't think the
limitations of some PC hardware should limit our goals for Linux.

Nigel Gamble                                    [e-mail]
Mountain View, CA, USA.                         http://www.nrg.org/