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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: AY9GkbwcuvwtDDhOdiqXeho8xuHBPDjWFeq7PjU+M5iCuvdw3t+gD6zEGe2HtBrDCO7VDAgmtNSA8XoKxwQKvA6dd2nSSlDUxaZx/b4pOnWs7w/GDVXaQr0uMPTOzxIzcvjOzskUygiYQjtY1hQNU2QauVJAFp1ORPxlaPZJLgin2aYH3c6urPlFhZI/4XDREturnjjMys1QsbMvEkvTDIOyqMFhtJgTxVCtPTmk64nhfpomRE5WLWC8/rJZ0lCoTVvFg7Dt9hwZ4V9Uj8xybRhrurmlVoW2eqRiQVBBx7uZWsw1wjbejhgSQAVoofn3I7TAd1kl91jCCmZdeTtwIAvxsh6ca30k21QDqH4ZP+H4ueU7rizvfBMusujMWdmFZH0zPzygdgRe8IkhJt4geda1XAGJUPVgo5x8ULkCOKLBWyOrKty9h8BkFuNyev30 X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Feb 2026 03:36:11.3337 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 66fa5d53-69f7-44e8-68ef-08de741f0540 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF000075F4.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SAWPR12MB999141 Hello Sebastian, On 2/24/2026 4:43 PM, Sebastian Andrzej Siewior wrote: > My question was initially is 1024 for max-nodes something that people > really use. It was introduced as of > https://lore.kernel.org/all/alpine.DEB.2.00.1003101537330.30724@chino.kir.corp.google.com/ > > but it looks odd. It might just one or two machines which are left :) I have it on good faith that some EPYC user on distro kernels turn on "L3 as NUMA" option which currently results into 32 NUMA nodes on our largest configuration. Adding a little bit more margin for CXL nodes should make even CONFIG_NODES_SHIFT=6 pretty sane default for most real-word configs. I don't think we can go more than 10 or so CXL nodes considering the number of PCIe lanes unless there are more creative ways to attach tiered memory that appear as a NUMA node. I'm not sure if Intel has similar crazy combination but NODES_SHIFT=6 can accommodate (16 socket * SNC-3) + up to 16 CXL nodes so it should be fine for most distro users too? -- Thanks and Regards, Prateek