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On Thu, 2007-06-28 at 18:45 +0200, Dieter Ries wrote: |
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> Hi, |
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> |
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> |
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> Hemmann, Volker Armin schrieb: |
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> > On Donnerstag, 28. Juni 2007, Simon Cooper wrote: |
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> >> whats with the NUMA stuff? |
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> > |
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> > nothing. If you only have once cpu with two cores, don't use it! |
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> |
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> What exactly does that mean? None of those : |
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> |
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> [*] Non Uniform Memory Access (NUMA) Support |
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> [*] Old style AMD Opteron NUMA detection |
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> [*] ACPI NUMA detection |
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> [*] NUMA emulation |
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> |
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> Or should one use the emulation. |
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> |
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> And is it suggested not to use NUMA only on amd cpu's, or is it just the |
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> same on core2duo processors? |
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> |
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> BTW, what is NUMA exactly? And when should one use it? |
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> |
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|
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Intel CPUs don't do NUMA, only AMD cpus do. However, you need at least |
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2 physical CPUs to actually do NUMA, and you also need memory attached |
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to each one. Most cheap dual CPU AMD boards don't actually have memory |
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hooked to both CPUs, only to one of them. If your board has banks of |
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ram (generally on either side of the CPUs) it probably does NUMA. |
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Otherwise, it doesn't. |
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|
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That said, enabling NUMA on a non-NUMA box doesn't really hurt, same as |
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enabling SMP on a non-SMP box. |
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|
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Daniel |
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|
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-- |
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