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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jan 2026 14:38:54.9083 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: bba1febf-138f-483b-7222-08de52b17a77 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: CY4PEPF0000EDD1.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB6117 On 13-Jan-26 7:54 PM, Gregory Price wrote: > On Sat, Dec 06, 2025 at 03:44:14PM +0530, Bharata B Rao wrote: >> Hi, >> >> This is v4 of page hotness tracking and promotion sub-system pghot. >> > > Just fyi, we haven't started real workload testing, but we're setting > up the process soon. Just wanted to let you know it's on the radar. > > We want to test this at the same time with some fixes we've been > working on for multi-tenant fairness in the demotion/reclaim path. Thanks Gregory for taking this up for testing. I am working on v5 with following enhancements: 1. Default mode: 1 byte per PFN for storing hotness info. NID isn't stored but promotion will be done to a default toptier node(specifiable via sysfs/debugs). Frequency and time are stored but due to paucity of bits, I will have to use some sort of bucketing scheme for storing time like how current hot page promotion logic does. 2. Precision mode: 4 bytes or 32bits per PFN where NID is stored in addition to time and frequency. 2 is completed and 1 is in the works. Once I get it working correctly, I will post v5. Since there were a few bugs in v4, I think it makes sense to start testing on v5 itself. Regards, Bharata.