Re: a joint letter on low latency and Linux

[Linus Torvalds]

On Thu, 29 Jun 2000, Larry McVoy wrote:
> 
> I guess the problem I have is that I don't see a clean way to make sure
> that no high latency events ever creep into the kernel.  I'm 100% in
> agreement with the idea that all code paths through the kernel should
> be short and sweet, but that isn't always the case.  All it takes is
> one misbehaving driver that hangs onto the CPU too long and you missed
> your deadline.

I agree. Badly written code will be a problem. The approach that the
patches so far have taken is to just add scheduling points all over the
map. 

> I'd rather support RTLinux than see lots of kludges being slipped into
> the generic kernel.

In many cases I just think that RTLinux is a worse fix than the disease. I
think RTLinux is perfect for those things that truly need latency
guarantees: no OS at _all_ in the way. But using it for "normal" stuff
like just streaming audio and video is overkill. They don't have
microsecond latency requirements.

		Linus