32-bit vs. 64-bit Benchmarks

[artik]

I have seen links from this forum to my article (amd64vsi386.pdf).

The main point of benchmarks that I had done was to test wide range of software - not few specific programs but verify common tasks that computers are used for (multimedia,servers,games,math,3D) and see what are the advantages, in certain cases there are but sometimes no.

I think one of the problems with most of benchmarks that they use "standard benchmark tools" - like FPU speed or RAM speed that compare different HW (the speed of RAM/FPU will not change on same HW). What you need to compare is "same software" compiled for different platforms.

So IMHO tests like "RAM speed" just irrelevant in case of 64 vs 32 comparison.

Best,
Artyom

[miknix]

Clearly, Ubuntu it's not the perfect distro for 64bit computing.
I think a more optimized distro should be used to benchmark 64bit VS 32bit, like Gentoo.
My Gentoo AMD64 laptop gives me far away better results in data compression, data encoding and source compiling!

Unreal Tournament has some specific maps just for 64bits platforms. Play them in x86 and feel the difference!

When talking about my developed apps that needs critical performance in execution time, using ACML in my AMD64 gives me more than 40% of speed increase.

[joshuapurcell]

Clearly, Ubuntu it's not the perfect distro for 64bit computing.
I think a more optimized distro should be used to benchmark 64bit VS 32bit, like Gentoo.
My Gentoo AMD64 laptop gives me far away better results in data compression, data encoding and source compiling!

Unreal Tournament has some specific maps just for 64bits platforms. Play them in x86 and feel the difference!

When talking about my developed apps that needs critical performance in execution time, using ACML in my AMD64 gives me more than 40% of speed increase.

From my previous post I showed that Edgy64 could see 4047512K, which is the most I have currently been able to get an OS to see. Do you also have 4GB of memory, and if so does Gentoo64 see more memory? I haven't tested this out yet.

[miknix]

No, sorry.

[joshuapurcell]

Thanks for the reply anyway. I'll install Gentoo64 and see how much memory it finds and make a post once it's done.

Clearly, Ubuntu it's not the perfect distro for 64bit computing.
I think a more optimized distro should be used to benchmark 64bit VS 32bit, like Gentoo.
My Gentoo AMD64 laptop gives me far away better results in data compression, data encoding and source compiling!

I hear this argument every once in a while, and I'm fully prepared to accept that Gentoo may be better than Ubuntu in some aspects. I'd like to see the results of your tests though if you have them, because without some tests or other types of proof it just comes down to the same old "which distribution you like better" argument, and we can find that discussion anywhere. In any area (but especially when it involves gaming), do you have some test results that show Gentoo64 is faster than Ubuntu64? I expect some things to be faster in Gentoo64 because most packages are compiled for the computer the OS is running on (if I'm not mistaken). But I want to know if there is actually a speed increase where it matters to me, and if any speed increase makes it actually worth it to move from Ubuntu and all the benefits that come with using this distribution.

[miknix]

In any area (but especially when it involves gaming), do you have some test results that show Gentoo64 is faster than Ubuntu64?

I'll try to benchmark my laptop soon as I can. My laptop graphics card burned out because the VGA cooler din't start. (ACPI BUG)
So I don't have any amd64 processor at hand right now

I expect some things to be faster in Gentoo64 because most packages are compiled for the computer the OS is running on (if I'm not mistaken). But I want to know if there is actually a speed increase where it matters to me, and if any speed increase makes it actually worth it to move from Ubuntu and all the benefits that come with using this distribution.

Yes, Gentoo builds all packages from source. But we can archieve major optimizations by choosing compiler specific flags for each package.

Meanwhile, a thread about this benchmark in gentoo forums was opened. I think you would like to take a look
http://forums.gentoo.org/viewtopic-t-349691.html

If you would like to try gentoo, AMD recommends (http://www.amd.com/us-en/assets/cont...docs/32035.pdf)
these CFLAGS="-O3 -ffast-math -funroll-all-loops -fpeel-loops -ftracer -funswitch-loops -funit-at-a-time"

Another interesting link: http://enterprise.linux.com/article....413209&tid=121
Look at these benchmarks and read the comments
These results, despite being gentoo based, are not optimal just because the packages were compiled with march=pentium4. march=athlon64 should be used instead.
This is what happens to most of binary packages based distros. They have generic (safe) x86_64 support.

[joshuapurcell]

mknix: Thanks for the very helpful information. This type of stuff is exactly what I was interested in to help me decide between Gentoo64 and Ubuntu64. I'll continue looking for some performance information and comparisons for the two distributions and post when I find some more information.

[MU_Engineer]

From my previous post I showed that Edgy64 could see 4047512K, which is the most I have currently been able to get an OS to see. Do you also have 4GB of memory, and if so does Gentoo64 see more memory? I haven't tested this out yet.

You will *never* see the "full" 4194304K as the kernel will reserve some of the RAM for itself. My 64-bit Gentoo box with 2GB RAM sees 2011MB. My 32-bit laptop sees about 1510MB out of 1.5GB. Every distro will see roughly the same amount of RAM as long as it is capable. A 32-bit distro will not be able to see much more than 3GB RAM as there is a 3GB/1GB user/kernel split set up in most 32-bit distros. If you recompile the kernel with PAE (64GB High Memory Support) you should see ~4GB. I did this on a 32-bit box running FC5 and I see about 4GB RAM now.

joshupurcell: Almost all Linuxes that run the same applications will run more or less the same speed. I run Gentoo and like it a lot, but to be brutally honest, it runs no faster than any other KDE distribution with unneeded daemons shut off. Gentoo is about configurability (and perhaps learning) but not speed, except in very odd cases (such as being able to tune a very specific number-crunching math app.) Gentoo is also a wonderful platform to develop on as you have a full toolkit and headers already there once you have the system up. If there is any speed to be gained from Gentoo, it's by cutting out stuff you don't need so there's less of a load on the system. The Gentoo devs are very good, but they're not magic. We are all bound by the limits of our hardware and the design of the common set of applications we all run like OpenOffice, gcc, KDE, and Gnome.

[cakey]

Did you use the 64 bit ut2004 binary?

[joshuapurcell]

You will *never* see the "full" 4194304K as the kernel will reserve some of the RAM for itself. My 64-bit Gentoo box with 2GB RAM sees 2011MB. My 32-bit laptop sees about 1510MB out of 1.5GB. Every distro will see roughly the same amount of RAM as long as it is capable. A 32-bit distro will not be able to see much more than 3GB RAM as there is a 3GB/1GB user/kernel split set up in most 32-bit distros. If you recompile the kernel with PAE (64GB High Memory Support) you should see ~4GB. I did this on a 32-bit box running FC5 and I see about 4GB RAM now.

I'm not expecting any Linux distribution to see all of the 4GB, but since there is so much difference between the three OS's that I've tried so far I wanted to see if there were any similar differences between two 64-bit Linux distributions. I would like to say that since both Edgy64 and Gentoo64 are both using the Linux kernel that would be enough to assume they will both see the same amount of memory. But I'm not sure about that since I have no idea what relevant options were on/off when compiling the kernels for these distributions, and I know the two distributions are using different versions of the kernel.

The 32-bit memory limitations are something I'm aware of, but I am surprised at the information you gave regarding PAE and 4GB of memory under Fedora Core5. I'll have to look into possibly recompiling my current kernel with PAE enabled before doing a reinstall and seeing if that helps out.