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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?efq1qG8YbownV1qedizJVwfQ0U4/DyOvOstyljwF6PbqQzjDOj2mKHxgLKVM?= =?us-ascii?Q?oVryya0igFnd13EokeNgn7x4+9LKn+ykhH1dTmD/cPn/p2/DO81r5ixY99lu?= =?us-ascii?Q?Ep61HDiobDVVzPVi+zrPnznhOBBZynSoOVpPPlRV2DCt09WFDJ+k5lnoGdCb?= =?us-ascii?Q?0G/Bc73YpJxmnmcrkPBBH7jPgKoBuwXibf1COHpiMeC8+8MT4edAvZMLsY8q?= =?us-ascii?Q?rDIUlEjDlH8yOi0jm6a6nHoIT7bh9H+Hc4zqC8zL/6DKM827rTyLrdj4+/D2?= =?us-ascii?Q?VqU3WBnGTcwwk7cCk1AZFJ2+5xG58ywd4dByefPAmVNXtCe+lA5hLjrp1HN3?= =?us-ascii?Q?/kCrtHMlB//o8xKFBV0rMnJGquH9TpFVmGcr2aFmOXEUklGiwjPdvrzTSQuS?= =?us-ascii?Q?crNp3wrOCRTb5lCpY9+N7F9gK48IHzAGKcJqDO2XpZH5BczkTSfp2J4+BTQ0?= =?us-ascii?Q?gY0JLHHSdvwACBuvNB3+MosMmjMcGgYJsB2A0G35Hl93A/aaMSLLLBH5/C9H?= =?us-ascii?Q?1A20K61Snv+THvYRE6VUvn4V5djOy2R8UZbhiwmKupbE3NkvJsDiHXRJa5bQ?= =?us-ascii?Q?WXNYYR3a9r9d1zqCtmhVosQ8mBZ9WY6L7vUEOcTrAAToSTAmVe/sZC9An0vH?= =?us-ascii?Q?cig+iTMGpwOlpQLSyXOJWTCDKJr5d1eTDq5bXVbs2/WEQcrIv7iCRgqe1i9Q?= =?us-ascii?Q?qUlG9PP2SekGEtcY5ZcWHGtEGf59FK/0uDbKC+P47pCzQCiWwZM1ISd8VbZ/?= =?us-ascii?Q?dMpgzDjbPgSUIi8EzMj47SJJo0e9pykzfR8WgH5IMGoP+VvaJn9bUUpzXuXT?= =?us-ascii?Q?ZZSqMGUvV/k+Cgba7ktq9mtMK0mVpSYlynv0shd+64cf4GSAaQSAszV9PJcV?= =?us-ascii?Q?1pOVAYCtIR4i7atzF8QwOMzCK25BsWIHGUGbt9WxEXqMCCpnna5jqD5/bRWw?= =?us-ascii?Q?s/1g8hwiykyIWsKA1Yvku4HpFvxgTL4Ct6MK2XcYtT2Tv9XQ7VlWMdOjvKoC?= =?us-ascii?Q?Ksp0W9vSMmDqvbh/ha413aINAScN3gxdnLCSZhZVWziFVAA2O06WO/oS4oXE?= =?us-ascii?Q?ZMpaQbGj4NsuitUd4uJcwWTep3g2Uo2haYVcanEReVb/yUNcMcN/Z90Q6O0A?= =?us-ascii?Q?D8yfSVshhD4hfCOgRkpJjxt31ro/JRwWs6kWz3qDyi220Yw3ybxNbtWgTd3z?= =?us-ascii?Q?qOhZoRrTBgmlX6xilBeNcq2DCbgaf1W/JqCGXXvOt07/v9rhiVHuu0QZ8LeU?= =?us-ascii?Q?3gYrTYxvMa8RJ6QrF33E0n0imPAOVtsCgI5sL+7Hzbsn05OwQSMrNQY6K3O1?= =?us-ascii?Q?bK0AXHtVtU9UhSYUAaDvTlTMKDMne/jGy49H7UX5f5FOw0qwidw6PK/DrqvV?= =?us-ascii?Q?0zh/AI4kW3YcliJZkO1mDvg/WzKSOvedLcV6APT3RZouANwgtSHGEK9/0Qdh?= =?us-ascii?Q?55aP6JTo8k35xU9ePejC/eQUdkKcH6Ansj8X+3qAzpaloZiq7dGjentrFJzl?= =?us-ascii?Q?ch6d6opodA636NHU6nc5y7XRmXlcORsPtKYSGi9PW8biki6QooknLyCgBCYr?= =?us-ascii?Q?pbOyuzDmjU3Xg48UmHpxwRGvTFMcxoSMSRBp0wH+9STL2K0xFnryLXwSiv9B?= =?us-ascii?Q?9/4y0HeL/2UMoG8DWICpbLCFtsxIigfHZoPcNa1YB562Z0YvMAQtUdEAL2VC?= =?us-ascii?Q?3zqbDK+aXetMWRbuRSjrLfga4/po0Saaqx7TThzKmrAyAIWR?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 85a10c3e-a2ab-4065-0b53-08df3052e0dd X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Oct 2026 15:41:02.9311 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: NwQtf4LNBYSBD7vi7Tq2bnWWLNXgFQTPWIPgi1kjK04Zcdm47o1mPLeErRlBnot8 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH1PPF0B4A257F6 On 19 Oct 2026, at 16:16, Gregory Price wrote: > On Mon, Oct 19, 2026 at 03:51:27PM -0400, Zi Yan wrote: >> On Mon Oct 19, 2026 at 2:48 PM EDT, Gregory Price (Meta) wrote: >>> if (kswapd_test_hopeless(pgdat) && >>> - next_memory_node(pgdat->node_id) < MAX_NUMNODES) >>> + num_node_state(N_MEMORY) > 1) >> >> Why does a runtime behavior, clearing kswapd hopeless state, depend on a >> static memory topology (excluding memory hotadd/hotremove in this >> context)? There is nothing telling us if a fallback node has available memory. >> >> Just reset it regardless. kswapd can go hopeless later if the node >> cannot be reclaimed. >> > > I mostly agree, but this was more of behavioral change than i was > outright willing to commit to in a stable backport. > > I can send a follow up commit to drop the check altogether if you > prefer - but I'm not sure we want to drop it outright in the backport. Yeah, for that specific Fixes, your patch works. Feel free to add Acked-by: Zi Yan > >> BTW, LLM also points out that kswapd_try_clear_hopeless(), called by >> direct reclaim, only clears hopeless when the node is balanced, but that >> rarely happens. So hopeless state can stay much longer if there is only >> one node. Adding Jiayuna, who added kswapd_try_clear_hopeless(), to gvie >> some insight. >> > > Yeah I have some additional things in my pile on the hopeless flag, but > i haven't gotten around to them. Got it. The above issue will have a separate fix I guess. Best Regards, Yan, Zi