Fast Pentium memcpy stuff

Robert L Krawitz (rlk@tiac.net)
Fri, 12 Apr 1996 16:57:05 -0400

First off, would everyone who uses this please send me email? I'd
like to set up a mailing list so I don't have to bother everyone on
linux-kernel who's perfectly satisfied with slow memcpy performance.

Secondly, I've started having problems with it (at least in the
routine that copies from system to user space; the others seem fine).
Specifically, make -j gets a lot of corruption (bogus source files) in
some of the newer kernels that didn't happen even as recently as the
low 1.3.8x's (I only got the usual sig11's that I also got without the
fast copy). This is only an issue with the _tofs routine; if I
disable that one and use the others (_fromfs, "regular" memcpy, and
zero_chunk) everything's fine (although read performance from the
filesystem drops a lot). I'd like someone else to do this to see if
this problem is reproducible or happens only on my system.

-- 
Robert Krawitz <rlk@tiac.net>           http://www.tiac.net/users/rlk/


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