Analysis: x86 Vs PPC 129
Gentu writes "Nicholas Blachford (engineer of the PPC-based PEGASOS Platform) wrote a long and detailed article, comparing the PPC and the x86 architectures on a number of levels: performance, Vector processing and Power Consumption differences, architectural differences, RISC Vs CISC and more. The article is up-to-date and so it takes the G5 into account too."
These arguments are so tired (Score:5, Insightful)
If you have x-platform software that will compile painlessly on either architecture, go for it, switch with each faster chip. But for most others, I doubt performance rants like these will make much of a difference. After all, how many Mac users switch to the PC just for the performance during those stretches when the PC has the upper hand?
Truly suprising colnclusion, OR NOT! (Score:5, Insightful)
What an unbiased opinion. Maybe we should really hear the other side too. I like the article for the wealth of info, and we all know the shortcomings of the x86 platform, but the conclusion seems to be biased.
Or is it just me?
"Desktop" weasel word. Where's the Opteron? (Score:2, Insightful)
Saying the Pentium 4 and Athlon XP are the current x86 chips, is just plain wrong. Those chips are obsolete except for very low-end (i.e. under $1k) systems. If you're building a x86 machine and your budget is approximately the same as the budget of a guy building a mid-range PPC system, then you have to be crazy to not get an Opteron, desktop or not. Thus, Opteron is the chip this author should be comparing to.
how long can x86 go? (Score:3, Insightful)
[Q] Small & Expensive = CISCRISC? (Score:5, Insightful)
When Microprocessors such as x86 were first developed during the 1970s memories were very low capacity and highly expensive. Consequently keeping the size of software down was important and the instruction sets in CPUs at the time reflected this.
So I'm puzzled. Perhaps someone can enlighten me on this.
If CISC is particularly appropriate for memory that is
Modern cache memories are, guess what,
Since main memory latency and BW are pretty limiting, I half expect that there's good argument to make very high performance systems live completely inside a large cache.
Re:These arguments are so tired (Score:3, Insightful)
Yes, and software is becoming more and more portable.
As the article observes, Linux (and open-source software in general) is not locked into the x86 architecture like Windows is. The use of server-side Java is growing, also architecture agnostic. Additionally, the web and web-based applications have shifted much of the work custom client applications used to do into the browser. Once again, architecture is doesn't matter.
The trend is that CPU architecture as a means of lock-in is declining, due those factors and many others. At some point, the cost of moving to another architecture will decline to near-zero, and the CPU business will shift to more of a commodity market, where people will buy on merit alone.
The only question is when it will happen; people have been predicting it for years (remember when NT ran on PPC, MIPS and Alpha?).
Right now, the PPC seems to win in some areas (power consumption, die size) and, barring architectural lock-in, it would probably take a large chunk of the Intel/AMD market.
Re:PPC (Score:3, Insightful)
Remember, electricity is pennies a KWh. Now, there are cooling considerations too, but even those are managable. In general, the highest operating expense of a company is not cooling or electricity but other factors like the facility, staff, or bandwidth.
Around here (Colorado), electricity is seven cents a kilowatt hour. Say a P4 @ 90W does the same work as a G5 @ 30W. That's a savings of 60W. Imagine the computer is on 10 hours a day, five days a week. That's a savings of 3000Whr (3KWh) or 21 cents a week. You save a total of $10.92 per year. Or, say the computers are on 24/7. That's a total of $36.69 per year.
Say an HP XW4100 system (P4 3.2CGhz) system does the same work in a CAD app as a dual 1.6GHz G5 system (remember, most CAD apps are not dual-processor optimized). The XW4100 is around $1500; the "low-end" G5 is $2000. At $36.69 per year (running 24/7), the G5 will pay for itself in 13.62 years.
On the Tclk myth (Score:3, Insightful)
Re:PPC (Score:3, Insightful)
Generally, they do not perform like the POWER4, UltraSPARC III, etc., for comparable power consumption. The Opteron is the closest bet for x86.
Remember, electricity is pennies a KWh.
Although $37 looks small, the savings scales with the company and can amount to thousands of dollars saved. Imagine an 8-way server ($300/year saved) or 32-way server ($1,200/year saved) or an office with 50 workstations ($2,000/year saved). That savings just might replace a broken photocopier or other budget-constrained items.
Power costs aren't something to laugh at, and conservation should be practiced in all aspects of a company (lighting, insulation, etc.). For self-employed people, it can mean an extra week's gasoline, for a large corporation, it can mean not laying someone off. These are real tangible benefits to buying low-consumption devices.
Re:PPC (Score:3, Insightful)
Imagine buying a G5 iMac desktop will save me $50/year in electricity bills, but the system costs $200 more than a comparable x86 machine. Then it takes four years for the energy savings to pay for the added equipment expense. Multiplied over 50 workstations, the effect is the same, only the numbers get bigger on both sides of the equation. Just because those 50 machines will save me $2500 annually, doesn't mean they're necessarily worth $10,000 more up front.
However, the energy assumption is a difficult one to make. Energy costs are volatile, generally only increase, and are not an insignificant variable expense for most businesses-- minimizing that expense is not a bad move.
Re:Truly suprising colnclusion, OR NOT! (Score:4, Insightful)
Well - today's RISC's aren't very RISCy anymore.
An example of where the guy goes wrong is in his discussion of the compilers. What he fails to understand is that one BIG reason that the Intel compiler is better than GCC is that the same kinds of compiler optimization that accounts for how the hardware schedules things work for both the PPC and the Intel architecture. This has been true since the original entry of the MIPs architecture for goodness sake. Intel KNOWS what the hardware is going to do, and built those smarts into the compiler! You can do the same thing for the PowerPC by the way..not saying you can't.
Nuff said - it was an interesting article but bowed to much towards RISC is Great - All Hail RISC bunch.
Re:On the Tclk myth (Score:3, Insightful)
We know that as chips get more complicated they get harder to scale to faster speeds. The P4 was a chipdesign that, from the beginning, was designed to scale--huge pipelines, etc (and the pipes are getting bigger too).
Now what's wrong with making a chip that is easy to scale?