Re: [Bug 350] New: i386 context switch very slow compared to 2.4

[H. Peter Anvin]

Followup to:  <[e-mail]>
By author:    Linus Torvalds <[e-mail]>
In newsgroup: linux.dev.kernel
> 
> Wow. There aren't many things that AMD tends to show the P4-like "big
> latency in rare cases" behaviour.
> 
> But quite honestly, I think they made the right call, and I _expect_ that
> of modern CPU's. The fact is, modern CPU's tend to need to pre-decode the
> instruction stream some way, and storing to it while running from it is
> just a really really bad idea. And since it's so easy to avoid it, you
> really just shouldn't do it.
> 

AMD, I believe, has an "annotated" icache.

	-hpa
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