Subject: Memory copy performance
To: None <tech-kern@netbsd.org>
From: =?iso-8859-1?Q?P=E5l_Halvorsen?= <paalh@unik.no>
List: tech-kern
Date: 01/29/2001 13:11:10
Hi!

I have performed an experiment looking at memory copy performance using
copyin, copyout and memcpy on an i386 machine.

My tests indicate that it is faster to copy data if the size is between
1kb and 8 kb. The performance drops dramatically at sizes >=16kb and =<0.5kb.

Why is this so? Is there some optimalization for these sizes?

-ph
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