Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 26 May 1997 01:00:46 -0400
From:      Charles Henrich <henrich@crh.cl.msu.edu>
To:        Brian Tao <taob@nbc.netcom.ca>
Cc:        freebsd-chat@FreeBSD.ORG
Subject:   Re: Pentium II-266Mhz
Message-ID:  <19970526010046.05547@crh.cl.msu.edu>
In-Reply-To: <Pine.GSO.3.95.970525164111.21528x-100000@tor-adm1.nbc.netcom.ca>; from Brian Tao on Sun, May 25, 1997 at 04:42:50PM -0400
References:  <19970522202155.61543@crh.cl.msu.edu> <Pine.GSO.3.95.970525164111.21528x-100000@tor-adm1.nbc.netcom.ca>

next in thread | previous in thread | raw e-mail | index | archive | help
On the subject of Re: Pentium II-266Mhz, Brian Tao stated:

> 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...  

Yep, thats been my gripe for a long time.  The PCI bus sucks, it needs to be
twice the bandwidth of the CPU (or more!) for growth, and memory access times
need to go down.  I would bet if someone did a formal study, that a huge
percentage of Intel cycles are spent waiting for loads..  Speed up the
Pentium(Pro/PII) without changing a thing, except the motherboad!

-Crh

       Charles Henrich     Michigan State University     henrich@msu.edu

                         http://pilot.msu.edu/~henrich



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19970526010046.05547>