Re: how can a newer processor have worse L1 cache?

Date	Thu, 07 Apr 2011 00:38:22 -0400
From	Yousuf Khan <bbbl67@spammenot.yahoo.com>
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Subject	Re: how can a newer processor have worse L1 cache?
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On 06/04/2011 9:17 AM, Anne Onime wrote:
> I have seen many peoples castigating the Prescott compared to
> the Northwood P4. We had a stretch of rainy days, so I tested
> some old PCs - I had a draw full of Pentium IVs to swap in them.
> One benchmark for L1 latency came out thus:
> Northwood 2 cycles
> Prescott 5 cycles
> Cedar Mill 4 cycles
> How did Intel bugger up the L1 cache?

Thinking back to my ancient history, it had to do with the fact that 
Intel was aiming for 10GHz back then, so they stretched the instruction 
pipeline stage on the newer P4's, and this affected their latency. 
Higher latency in exchange for higher throughput. They expected that the 
greater clock rate would make up for the increased relative latency, by 
keeping the absolute latency the same.

	Yousuf Khan

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how can a newer processor have worse L1 cache? Anne Onime <anonymous@rip.ax.lt> - 2011-04-06 15:17 +0200
  Re: how can a newer processor have worse L1 cache? Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2011-04-07 00:38 -0400
  Re: how can a newer processor have worse L1 cache? "Jim" <jim@wtf.invalid> - 2011-04-07 05:48 -0400
  Re: how can a newer processor have worse L1 cache? Robert Myers <rbmyersusa@gmail.com> - 2011-04-10 15:19 -0400

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