Hi all,
I want to know is there any official recommendation from AMD for choosing a linux distribution for new magny-cores (8 cores)? Which one is optimized for opteron? centos, redhat enterprise, debian amd64, ....?

Any remotely modern Linux distribution will work well for Magny-Cours. Most Linux distributions are simply compiled for generic 64-bit CPUs (no "-march" being set, no SSE instructions beyond SSE2) so they well run on anything from an original 130 nm single-core Hammer Opteron to a Magny-Cours and everything in between. Linux tends to perform pretty well on 64-bit AMD CPUs, so I wouldn't really worry about it.

If you are still really concerned with optimization, you can recompile the kernel for your particular CPU family by downloading, installing, and compiling the kernel sources. You will want to set the CPU family and vendor to "Opteron/K8/Hammer" in the Linux kernel config and append 'CFLAGS="-O2 -pipe -march-amdfam10"' when you execute the make instructions. If you want even more optimization, run Gentoo Linux and compile everything from scratch with those CFLAGS in your /etc/make.profile to make everything specifically optimized for your CPU. You won't see a huge gain from doing so in most applications, but you can do it if you really want to.

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I would have chosen Gentoo as you compile all code instruction sets and amd64/128bit optimizations making the worlds most stable most speedy most robust OS.

With 8 and 12 core 128bit interface system compiling is fast so installation time is cut down massively its also a good burn in for your new system to set in the components. CUDA source work seamless with Gentoo takes a bit of tweaking as with all source code but hey its awesome.

Note for ATI stream there source is very beta and i mean very beta but i have managed to get it compiled and do something took a while but it does work so if you choose ATI on linux be prepared to venture into the unknown lol

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I see a rainbow of colours between black and white.

I do not work for AMD.


Oracle has a complete line of free Operating Systems that 'scale' well and they also offer their own Linux compiles that they tweak for Enterprise use along with numerous other free Software. You only pay for Support (and Support is not mandatory for obtaining a free Operating System (and other software too)).

I also recommend Debian Linux.

If either of the above do not scale wonderfully (for many 100's of Cores with Solaris) that is a Bug (as long as your Hardware is capable) and you can file a Report (for free) and be certain to get an answer (and likely an Update) without too long a wait (assuming you do not pay).

Redhat is pretty much up there with being able to support the latest AMD tech. You get the OS for free but need to pay for a year's support if you want any upgrades and any of the decent stuff! What you end up going for should be something that you need to decide for yourself. Look at the distro you prefer and then go with that one if it is supported I guess.

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The opinions expressed above do not represent those of Advanced Micro Devices or any of their affiliates.

I would have chosen Gentoo as you compile all code instruction sets and amd64/128bit optimizations making the worlds most stable most speedy most robust OS.

Gentoo is an excellent OS, but in all truth, it's main selling point is configurability, not speed or reliability. Gentoo is the OS to go to if you need something done just so. I use Gentoo for my HTPC since it is by far the easiest way to get a minimal MythTV frontend with just the features I want and nothing more.

There is usually not much of a gain in going from generic binaries compiled for any x86_64 CPU to your specific CPU. A few specific programs might benefit from being compiled with a non-GCC compiler, but you want to do that outside of the package manager so that you don't compile some other program's dependency with the non-GCC compiler and break your system. I speak from experience on this issue with using ICC to try to compile a few programs within Portage for a speed boost. JUST DON'T DO IT. Gentoo is a rolling release and you can (and likely will) break things from time to time as you upgrade libraries and such. You can use revdep-rebuild and emerge -e system/world to rebuild programs in case of ABI breakages, but that can be a real pain in the butt. I'd throw my lot in for Debian stable being the most robust Linux distribution since it undergoes extensive testing and has a very well-proven track record of reliability.

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