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J. Roeleveld wrote: |
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> On 4 November 2015 13:14:18 CET, hw <hw@×××××.de> wrote: |
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>> |
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>> Hi, |
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>> |
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>> how do I know whether xen uses NUMA or not? It says in dmesg: |
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>> |
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>> |
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>> [ 0.000000] NUMA turned off |
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>> [ 0.000000] Faking a node at [mem |
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>> 0x0000000000000000-0x0000000040068fff] |
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>> |
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>> |
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>> and 'xl info -n' shows two nodes: |
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>> |
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>> |
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>> node: memsize memfree distances |
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>> 0: 14656 3304 10,20 |
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>> 1: 23424 7792 20,10 |
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>> |
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>> |
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>> which could be right --- though I would expect each node to have 12GB |
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>> rather than these weird sizes. |
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>> |
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>> So is NUMA turned off or not? Is it even possible to turn it off when |
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>> it's |
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>> enabled in the BIOS? |
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> |
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> If BIOS has it enabled. Then the OS still beeds to support it. |
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> |
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> Recent Xen has support for it. |
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Is there any way to find out if it's actually made use of? |
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> As for the non uniform spread of the memory. It depends how the memory modules are placed in the mainboard with regards to the Numa nodes. (CPU) |
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The memory is evenly spread. The server has two CPUs with 6 memory banks each. |
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All banks for each CPU are loaded identically. Hence two NUMA nodes would make |
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sense, and each of them should see/have 12GB (now 14 each because I changed out |
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the server because it kept crashing/freezing/becoming unreachable even after the |
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software updates). |
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