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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: i9NbUQWgi2Yy1fB9m44ukE4hXdR9VVgMARI5U3ubhIA63goWVvRz/DQm77x5LtspRptxNOIH2zsDGq0842B3RAIcllGdY0cr5J7yFSDJqlSF0KzBwK0d2DkVdyknGqCuUB34osNwvfqMQMcSYAmFZ32qOVdSp1qwjXtsc6v4jr0YlmZMDcIeFch+LpkZKltMdaLbbLPfldxRqPNNFtP49ahbdQJZx8LRyFQXe/v6reyvlgMmLEQiBGXvDYRUvpygWhlY35SB9oAVoyBePx4CaCo3auKF3UBsUHrT5jyTRrfzv46L/BTQaRMGGxl8l7TJSHf4l4ve3Fnz1zbdwDT/qEM0WyWiUovn/xziHFbEkYp+Zfg5uCxUnr9z7VkDQLS4SwiL/RgI0sGa0WBCk1d1kK7m+DAeCqOoLXQTpfVqvb7cv6OYBXNVYvcsyGCBS92Y X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Apr 2026 15:52:08.2524 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 0a912c20-9d59-4d61-f3e5-08de9586ca29 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=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CH2PEPF00000145.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PPFA8EB66EE9 Hello Chenyu, On 4/8/2026 5:05 PM, Chen, Yu C wrote: > We haven't tried breaking it down further. One possible approach > is to partition it at L2 scope, the benefit of which may depend on > the workload. I fear at that point we'll have too many cachelines and too much cache pollution when the CPU starts reading this at tick to schedule a newidle balance. A 128 core system would bring in 128 * 64B = 8kB worth of data to traverse the mask and at that point it becomes a trade off between how fast you want reads vs writes and does it even speed up writes after a certain point? Sorry I got distracted by some other stuff today but I'll share the results from my experiments tomorrow. -- Thanks and Regards, Prateek