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From: Maxim Sobolev <sobomax@FreeBSD.org>
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To: Chuck Swiger <cswiger@mac.com>
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Cc: freebsd-current@FreeBSD.org, freebsd-arch@FreeBSD.org
Subject: Re: [PATCH] Mantaining turnstile aligned to 128 bytes in i386 CPUs
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Chuck Swiger wrote:

> Unfortunately, there are simply different tradeoffs between mechanisms 
> for copying depending on whether you want to use or avoid 
> using/thrashing the L1/L2 caches, whether the data is cache-aligned, and 
> so forth; the CPU can't infer what you want to occur-- you have to tell 
> it.  I find it interesting that some of the architectures (PA-RISC, 


Well, of course there are some special cases, but in general there 
should be some baseline suitable for most of uses. That's why we (and 
most other operating systems) only provide single version for the 
mem*(3) APIs.

-Maxim