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x86 vs PPC Linux benchmarks

Posted by Hemos on from the testing-the-hardware dept.

Jay Carlson writes "We've all heard about how Apple's hardware is really fast compared to PCs. ("Supercomputer!" "Twice as fast as a Pentium!" "Most powerful laptop on the planet!") So, if you *aren't* going to use Photoshop and Final Cut Pro, how fast is it? I care more about integer apps like compilers, so I did some careful benchmarking of a few x86 and PPC Linux boxes. Submissions welcome."

9 of 269 comments (clear)

  1. Benchmarks are so controversial by Anonymous Coward · · Score: 5

    Instead of pitting his machines against one another, he should've assembled them into a BEOWULF CLUSTER so they could WORK TOGETHER.

  2. No, not really. by devphil · · Score: 5


    Hi. I'm a GCC maintainer. I don't work on this part of the compiler, but I can speak to this point:

    Its opptimized for the x86.

    Nearly all of the optimizations in GCC are not machine-specific. Those kinds of optimizations, ones which are specific to the processor, are called peephole optimizations, and while every little bit helps, they don't make that much of a difference. The big ones are done at an intermediate level, before the compiler "knows" what processor it's using and starts to chunk out the opcodes.

    More specifically, unlike the Linux kernel, glibc, and other major projects, GCC is not designed for and targeted primarily at Intel chips. The x86 is just one more back-end like any other; sometimes it falls behind and sometimes it pulls ahead, development-wise.

    Those chages may not have been rolled back in to the tree yet,

    Some have, some have but won't be in the upcoming 3.0 release in a few weeks, and some are yet to come.

    The biggest problem is that many of the really cool optimizations -- the ones that make a big difference and aren't CPU-specific -- have been patented by IBM and other major players.

    --
    You cannot apply a technological solution to a sociological problem. (Edwards' Law)
  3. Examples? Suuuuuure.... by devphil · · Score: 5


    I can give you over a thousand examples, with the help of our f[r]iendly patent office (my tax dollars at work). Just go to http://www.uspto.gov/, look under the green Patent Grants area, follow the Advanced Search link, and search on "compiler and optimization". Doing this today, I got 1,261 patents, but some of them don't apply here.

    Er, that is to say, I got 1,261 search results each representing a patent. I don't have 1,261 patents myself. :-)

    --
    You cannot apply a technological solution to a sociological problem. (Edwards' Law)
  4. The Three types of Lies by Szynaka · · Score: 5

    Lies,
    Damn Lies, and
    Benchmarks

  5. Nothing really new here, is there? by Sir+Joltalot · · Score: 5

    I read through these comments and get the impression that slowly a conclusion is being reached: PPC-type hardware is good for some things, x86 hardware is good for others. Nothing really new there, is there? For running Linux, it seems from this little (and far from in-depth) benchmarking session that PCs are a bit better, especially given costs. You can probably get a 1.2GHz Athlon box for the cost of a 533MHz G4, and it'll be better for Linux, so if you run Linux, why not?

    MacOS X, stuff like Maya, Final Cut Pro, etc. etc. quite obviously runs better on PPCs, barring some strange circumstances. I imagine that with enough "brute force" (RAM, dual processors, etc.) one could get a PC to run this stuff faster than a Mac.. but what's the point? You might as well just keep it simple and buy a Mac that'll run it pretty well outta the box.

    I agree though, that cost is an important consideration. With 760MP around the corner, if it ever does surface in quantities making it available, dual Athlons might give dual G4s a bit of a whippin', especially considering AMDs prices as of late. In general I find you can buy a PC with a much faster proc, more RAM, etc. for the same cost as a Mac from the Apple store.

    Still, even a 1.2GHz Athlon would probably choke on OS X, and the G4 will at most hiccup...

    --
    "Caffeine is not an option. Caffeine is a way of life."
  6. I do this every year... by John+Carmack · · Score: 5

    I wind up doing my own internal PPC vs X86 benchmarks almost every year.

    I'll set up whatever current game I am working on to run with the graphics stubbed out so it is strictly a CPU load. We just did this recently while putting the DOOM demo together for MacWorld Tokyo.

    I'll port long-run time off line utilities.

    I'll sometimes write some synthetic benchmarks.

    Now understand that I LIKE Apple hardware from a systems standpoint (every time I have to open up a stupid PC case, I think about the Apple G3/G4 cases) , and I generally support Apple, but every test I have ever done has had x86 hardware outperforming PPC hardware.

    Not necessarily by huge margins, but pretty conclusively.

    Yes, I have used the Mr. C compiler and tried all the optimization options.

    Altivec is nice and easy to program for, but in most cases it is going to be held up because the memory subsystems on PPC systems aren't as good as on the PC.

    Some operations in Premier or Photoshop are definitely a lot faster on macs, and I would be very curious to see the respective implementations on PPC and X86. They damn sure won't just be the same C code compiled on both platforms, and it may just be a case of lots of hand optimized code competing against poorer implementations. I would like to see a Michael Abrash or Terje Mathison take the x86 SSE implementation head to head with the AltiVec implementation. That would make a great magazine article.

    I'll be right there trumpeting it when I get a Mac that runs my tests faster than any x86 hardware, but it hasn't happened yet. This is about measurements, not tribal identity, but some people always wind up being deeply offended by it...

    John Carmack

  7. With Linux, hardware performance doesn't matter by Rosco+P.+Coltrane · · Score: 5

    Everybody knows Linux is so fast it can execute an endless loop in 5 seconds flat.

    --
    "A door is what a dog is perpetually on the wrong side of" - Ogden Nash
  8. More work per clock. by abumarie · · Score: 5

    I don't thnk that you will ever get an agument from anyone over how very, very, very badly Motorola has messed up with being unable to deliver faster versions of the PowerPC. However, you should look at a couple of issues with these benchmarks: 1) 450/733 = .61 and 533/733 = .72. Thus any scores over .61 and .72 respectively, indicate that the PowerPC is doing more per clock cycle than then PIII. If Motorola can ever get their act together (and that is not a certain), normal code on the PowerPC will run every bit as fast and faster than the x86 processor. Combined with the fact that the PowerPC has a nice quiet and fairly energy efficient air-cooled chip you might have some nice machines. Unfortunately, all benchmarks can have some rather un-intentional bias. My 1.2 Athlon would do 105 Scimarks in Windoze 98, 113 Sciemanrks in Wine under Redhat, and 119 under Windoze 2000 for Tim Wilkin's Science Mark benchmark. Same machine, same memory, same disks, etc. the only difference was the os. Even given the same os, the tweaks that it goes through are also a function of the author's machine. Please pass the salt, I need a grain.

    --


    Sex is heriditary, if your parents didn't have it chances are good you won't either.
  9. The tests that matter to me by statusbar · · Score: 5

    http://www.jdkoftinoff.com/eqtest.tar.gz
    (gpl'd with source)

    450 mhz g4:
    1.7 gigaflops with altivec
    410 megaflops without altivec

    500 mhz pentium:
    220 megaflops

    --jeff

    --
    ipv6 is my vpn