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> -----Original Message----- |
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> From: Mark Kirkwood [mailto:markir@××××××××××××.nz] |
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> Sent: 31 January 2007 23:49 |
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> To: gentoo-user@l.g.o |
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> Subject: Re: [gentoo-user] Symlinking /usr/portage/distfiles |
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> |
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> |
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> Boyd Stephen Smith Jr. wrote: |
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> > On Wednesday 31 January 2007 09:58, Alan McKinnon |
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> > <alan@××××××××××××××××.za> wrote about 'Re: [gentoo-user] |
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> > Symlinking /usr/portage/distfiles': |
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> >> On Wednesday 31 January 2007, Bo Ørsted Andresen wrote: |
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> >>> Furthermore Pentium 4 is a joke (it performs horribly). A 2 GHz |
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> >>> (Dothan I presume) Pentium-M should be faster than a 2,8 |
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> GHz Pentium |
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> >>> 4. My timing is for an 1,6 GHz (Banias) Pentium-M btw. |
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> >> This sounds odd, but I'm not a cpu expert so can't really |
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> comment. Care |
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> >> to elaborate on why the P4 performs so horribly? |
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> > |
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> > The instruction pipeline is very long, the CPU <-> RAM |
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> bandwith is quite |
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> > small, and the pipeline has to be emptied any time the |
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> branch predictor is |
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> > wrong. While the pipeline fills, the CPU works but no results are |
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> > visible. |
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> > |
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> > Hz has never been a complete trump of other issues affecting CPU |
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> > performance, but is always a factor to consider. (Among |
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> CPUs that are |
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> > otherwise identical, higher Hz wins.) |
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> > |
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> |
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> Also Pentium-M has a lower latency L2 cache than P-4. With respect to |
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> pipeline lengths I was curious to see what they actually |
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> were: P-4 has |
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> 20 stages, P-M has.. err... < 20 stages (Intel won't say exactly!). |
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> |
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> I found this an interesting read for those of you interested in this: |
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> |
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> http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2342&p=1 |
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> |
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> Cheers |
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> |
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> Mark |
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At the risk of pulling this topic a little more off-topic - the P-M vs P-4 is an interesting case of a Pentium 3 chipset with a die shrink outperforming a P-4. |
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The Intel Core (2) Solo/Duo CPUs are based on the Pentium M as well. Netburst is pretty much dead afaik. |
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-- |
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djn |
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|
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Disclaimer: I represent no-one else in my emails to this list. Use any advice given at your own risk. |
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-- |
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