Subject: Re: mysql4 error
To: sp4rc <sammyshome@gmx.net>
From: Michael L. Hitch <mhitch@lightning.msu.montana.edu>
List: port-alpha
Date: 08/22/2005 10:19:54
On Mon, 22 Aug 2005, sp4rc wrote:

> > machdep.unaligned_print=1

  This should be 'machdep.unaligned_print=0' if you don't want the
messages printed.

> Now everything works as it should, but the unaligned access error looks
> pretty ugly and gives me a strange feeling, cause this should become a
> production server... any other hints on this?

  The unaligned access occurs because most programmers don't care about
(or don't even know about) alignment constraints.  The i386 processors
will happily load and store on unaligned boundaries and the only penalty
would be performance.  The alpha requires quad word loads and store to be
on a quadword boundary, but the NetBSD kernel has the ability to handle
the faults and 'fix' them up.  This will affect performance if there are
very many of them.

  To properly fix this, someone needs to identify the places in the mysql4
code where the unaligned accesses occur and redo the code to do properly
aligned memory accesses.

--
Michael L. Hitch			mhitch@montana.edu
Computer Consultant
Information Technology Center
Montana State University	Bozeman, MT	USA