Author: Tom Kerrigan
Date: 10:43:16 06/14/00
Go up one level in this thread
On June 14, 2000 at 07:02:47, Adrien Regimbald wrote: >Hello, > >> <clip> >> Later this year, Intel plans to launch a new PC processor code-named >>Willamette, which it says is based on a completely revised architecture from >>today's Pentium III. Intel said it will debut the processor at a clock speed of >>1.4GHz. >> <clip> >> >> When will this end?...ie..how fast can a processor possibly run >> at room temperature? > > >I'm overjoyed to hear this! ;) I have been getting sick of the strategy of >making constant tiny improvements to the existing architectures - a move to a >completely new architecture would be tremendous! > >From my classes on architecture, there were a lot of _very_ interesting >optimizations done to CPU architecture and strategies at the start of the PC >boom. Lately though, it has just been a mantra of "smaller smaller smaller, >more more more!" with no interesting advances made - I can't wait to see what >they've done for the new architecture :) There are two interesting things going on with the Willy: 1) Trace cache. This replaces the instruction cache. Instead of caching main memory, it stores decoded instructions in the order that they're run. The advantage is that instruction decode is eliminated in many performance-critical situations. The disadvantage is that a trace cache has to be several times bigger than a regular I cache to store a similar amount of code. Also, because instruction decode is often eliminated, the Willy will only have one decoder. So in cases where branch prediction isn't doing well, the decoder will be a bottleneck. 2) Double-pumped ALU. The ALU is designed to run on the rising and falling edge of the clock, which means that it effectively runs at 2.8GHz while the rest of the chip runs at 1.4GHz. This is probably so the ALU frequency isn't bounded by the speed of addition (or some more complicated ALU op). One other thing to note is that the pipeline is now 20 stages, so any branch mispredictions will basically result in disaster. It'll be interesting to see if the Willy is significantly faster than the PIII/Athlon... -Tom
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.