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Date: Sun, 25 May 1997 16:42:50 -0400 (EDT)
From: Brian Tao <taob@nbc.netcom.ca>
To: Charles Henrich <henrich@crh.cl.msu.edu>
cc: freebsd-chat@FreeBSD.ORG
Subject: Re: Pentium II-266Mhz
In-Reply-To: <19970522202155.61543@crh.cl.msu.edu>
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On Thu, 22 May 1997, Charles Henrich wrote:
> 
> 8:13pm crh> dd if=/dev/zero of=/dev/null bs=1m count=1000
> 1000+0 records in
> 1000+0 records out
> 1048576000 bytes transferred in 9.969560 secs (105177762 bytes/sec)
> 
> 8:14pm crh> dd if=/dev/zero of=/dev/null bs=128k count=8000
> 8000+0 records in
> 8000+0 records out
> 1048576000 bytes transferred in 4.389535 secs (238880886 bytes/sec)

    I presume the first involves the CPU going to main memory, while
the second fits entirely in L2 cache?  What's the bandwidth over a PCI
bus?  132MB/sec?  It looks like the CPU can push almost twice that.
Time for a 100-MHz bus or a separate CPU-to-RAM bus...
-- 
Brian Tao (BT300, taob@netcom.ca)
"Though this be madness, yet there is method in't"