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Double-Whammy Look At The Pentium 4
SystemLogicNet writes: "We at SystemLogic.net have just taken a technical look at the Pentium 4 architecture. In the article we go over all the basics that all the other sites cover like the double pumped ALUs, iSSE2, the longer pipeline, etc, but in addition we have some discussion about how different program structurings have an impact upon the design, and performance of the Pentium 4. One of the major areas where this comes into play is how complex data structures interact with the underlying philosophy that the Pentium 4 is built upon -- extreme bandwidth. This Pentium 4 technical background can be read over here. At the same time, we've done a rigorous analysis, including benchmark description and discussion regarding the Pentium 4's performance, and this can be read over this way."
Umm... This isn't a very good analogy. Imagine instead:
STOP . AMERICA . NOW
Tom's Hardware Guide or AnandTech
Sorry, but comparing a 1.1gig/200Mhz FSB Athlon to a 1.7gig P4 is laughable at best. What hardware review site uses a processor that's over a year old (Athlon 1.1gig/200FSB) in a comparison to one of the latest processors from the competition?
also, note that the 1.7 ghz p4 has a 600 mhz advantage over the 1.1 ghz athlon and usually the performance difference was only 10-40%. the p4 has over 50% more processor mhz than the athlon. what an unfair comparison, especially when the 1.33 ghz athlon is out and available for purchase. processor mhz for processor mhz, the athlon beat the p4.
The point of the extremely long (20-stage) pipeline of the Pentium 4 is the ability to reach extremely high clock speeds - much higher than the Athlon could ever reach. Of course, Mhz-for-Mhz, the Athlon is going to beat the Pentium 4 performance-wise, but it wouldn't tell us anything except the obvious differences in the two's design philosophies.
Light a fire for a man and he'll be warm for a day. Light a man on fire and he'll be warm for the rest of his life.
That is a much better explanantion, and now in respone to the original comment: it is nearly impossible to criticize that "miss rate" without actually going through the design process.
Something like Patterson & Hennessy would explain the classic tradeoff well. If you make a lower miss rate (imagine 9.5 out of 10 are hits), the time for hits goes up slightly. Now the main question becomes, what is the "common case".
The most important thing before you whine about some processor is to know the design process. Is missing 1 out of 20 times (but hit-time taking twice as long) better? Is missing 1 out of 7 times (but having a lightning-fast hit-time and tolerable miss-time) better? As a /.er there's really no room to say "thats so bad" unless you actually sat at Intel/AMD, went through the design process, and there was a better option for your mix of instructions.
Did you just cut and paste a press release onto the front page of Slashdot?
I sure hope you Slashdot isn't selling Front Page space to any little company that pays...
As an end user in the market for a new box based on p4 or athlon tech, I appreciate why he thinks the P4 sucks but I tend to think of two things that bias his judgement.
1) He's writting in assembly.
Any change that doesn't rely on x86 basics he's grown to love will likely be considered by him as bad. Eg. "... and even went so far as to expect developers to rewrite their applications to make use of the Pentium 4." The assembly language programming paradyne that he has embraced is not as conducive to rewritting so it's a chore. If he was writting in C and using asm for the most preformance intensive functions as is now standard practice for the non lazy (who know their target platform and optimize for it)it would not be such a chore. Perhaps if he used an Intel compiler plugin that optimizes for the P4 he would not be complaining. Should he have to do so? Nope, but it seems to be the way everything is heading whether you look at AMD or Intel. Also with AMD embracing functionality of SSE2 on their newest processors this is not going away.
I love asm, but most people would not try to write a modern office suite in it. It's a shame but it's the way things are. I wish more programmers of commercial applications coded better but I don't think this is going to get resolved anytime soon, unless we move more to an appliance architechure where resources are both well defined and limited or go opensource. I'm not holding my breath.
2) It sounds like as an early adopter he got burned on price. There was a time (11 months ago?)where the p4+rdram was about 3.5 times the cost of an athlon+sdram. If you look at the present it's more like 2.1 times the cost for a p4+rdram vs an athlon+ddr memory. That is still a sizeable chunk but remeber the cpu and memory just part of the equation. There's still case,ps,motherboard,storage and yes the OS and productivity license which despite being in a Windows dominated world is likely to be the first thing cut to save costs. It's already happened on the low end and the highend, and I think it's only a matter of time before it happens on the mid end.
As a side note it's interesting to once again hear the arguments for and against thermal protection. I think the arguments both have their points, but I think it would be better to have it, but also be able to turn it off from the BIOS. AMD's new chips will have the integrated thermal diode so really the issue is will endusers be to easily configure it manually.