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On Thursday, 23 September 2021 17:32:46 BST Charlotte Delenk wrote: |
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> On 9/23/21 18:30, Grant Taylor wrote: |
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> |
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> > On 9/23/21 4:39 AM, Miles Malone wrote: |
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> > |
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> >> You'd need NUMA if you had a NUMA machine. In current context, that |
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> >> would be either a) a dual socket system, b) an amd threadripper, or |
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> >> c) some of the really high core xeons. If your motherboard doesnt |
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> >> have certain memory banks allocated to certain processors or cores, |
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> >> you're probably not running a NUMA machine. |
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> > |
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> > |
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> > |
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> > Will a kernel without NUMA support boot and run on a system that has a |
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> > NUMA architecture? |
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> > |
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> > |
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> > |
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> > If it will boot and run, does it simply do so in a sub-optimal way? |
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> |
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> Pure speculation for this one but if it works it's probably only going |
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> to detect part of the memory and some of the devices and one cpu, since |
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> the other resources are physically connected to the other cpus. |
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> |
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> > |
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> > |
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> > Flipping the coin on the other side, is there any negative effect |
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> > (other than kernel size / lines of code / attack surface) for having |
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> > NUMA support enabled on a non-NUMA system? |
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> |
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> There is no meaningful downside to leaving it enabled, it's enabled in |
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> many distribution kernels for a reason. |
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|
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I've booted a kernel with no NUMA config, and it seems to run fine on this |
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single-socket Ryzen motherboard. I just get the one entry in dmesg: |
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|
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$ dmesg | grep -i numa |
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[ 0.297998] pci_bus 0000:00: on NUMA node 0 |
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That's it. I'm running five BOINC projects, some of which run on vbox, so on |
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this motherboard it seems clear that I don't need NUMA. |
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-- |
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Regards, |
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Peter. |
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