Also seeing 2 x quad-core system slower that 2 x dual core

Gavin Atkinson gavin.atkinson at
Fri Nov 30 07:52:42 PST 2007

On Fri, 2007-11-30 at 09:44 -0500, Jim Pingle wrote:
> This may be a silly question, but have you tried reducing the RAM on the
> quad core machine to 4GB so the machines match in that respect as well?
> I seem to recall a thread a while back about someone who had slowdowns in a
> certain situation with large amounts of RAM (>4GB).

This was with the Intel 965 chipset, and was fixed with a BIOS upgrade,
something to do with the way the BIOS set cache info up about memory
above 4Gb.  A BIOS upgrade may be worth trying.

Removing memory from the slow one toleave it with 4Gb may be a useful
datapoint.  Note that I don't think you can just set hw.maxmem as that
makes no guarantee as to *whicch* physical 4Gb will get used.

Finally, I assume you are using FreeBSD amd64 and not i386 in PAE mode?
Posting dmesg outputs from both systems somewhere might be useful, I
can't see it in the previous posts.


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