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charset=us-ascii Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 6CE8F140008 X-Stat-Signature: jyo4517g9aihxsd1u39hd17q575jzjtt X-HE-Tag: 1740570686-654087 X-HE-Meta: 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 pHsLMGy8 u0LYZ0thcio+GbkT0Rc5DtJ6bOTo1vPxfPK/+5xCOP3uft5lkYTTlqgrZdeDUw8jyi5ZgHNAToMiKKih5DMzmeT9W7UHGPh4Qw9ZxgJgsVQRlUT++HreTqWRcKhxPMLqAvwdR0m0DvOCZEiI9LV5faz48cxKyZtt0ckRERiFR3WfxYONXlGkGz280keZ+rFYrfBDv+IHxAznOVoKV8k3jcgn6QUwG1YEFnceaOg4Gj73PODhMXzV4KMouViL3+cPu693juWGLLyXwEYiDRzR08x3gERemhFzwYx/bKrMT211roC56m7oPSHJoWNS7ZwEENElILRQvEUsLhDd29a7k/S8twOGiM64VsrOHPJI5LwKo7I0f3dBB/w7okUDHh7yvTQlelnQsYx+NGlKNzkBVeNKGqEt4+OjHek6+Nr1RmW14Zo07SswS8mpvprcoWJFcBfKEaizycNVqthFmlYDY45b/N4bQjM+d08QOqw/mJoPwiCQ= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 02/26/25 at 12:00pm, Michal Hocko wrote: > On Wed 26-02-25 11:52:41, Michal Hocko wrote: > > On Wed 26-02-25 18:00:26, Baoquan He wrote: > > > On 02/26/25 at 07:54am, Michal Hocko wrote: > > [...] > > > > In any case 96a5c186efff seems incorrect because it assumes that the > > > > protection has anything to do with how higher zone is populated while > > > > the protection fundamentaly protects lower zone from higher zones > > > > allocation. Those allocations are independent on the actual memory in > > > > that zone. > > > > > > The protection value was introduced in non-NUMA time, and later adapted > > > to NUMA system. While it still only reflects each zone with other zones > > > within one specific node. We may need take this opportunity to > > > reconsider it, e.g in the FALLBACK zonelists case it needs take crossing > > > nodes into account. > > > > Are you suggesting zone fallback list to interleave nodes? I.e. > > numa_zonelist_order we used to have in the past and that has been > > removed by c9bff3eebc09 ("mm, page_alloc: rip out ZONELIST_ORDER_ZONE"). Hmm, if Gabriel can provide detailed node/zone information of the system, we can check if there's anything we can do to adjust zone->lowmem_reserve[] to reflect its real usage and semantics. I haven't thought of the whole zone fallback list to interleave nodes which invovles a lot of change. > > Btw. has 96a5c186efff tried to fix any actual runtime problem? The > changelog doesn't say much about that. No, no actual problem was observed on tht. I was just trying to make clear the semantics because I was confused by its obscure value printing of zone->lowmem_reserve[] in /proc/zoneinfo. I think we can merge this reverting firstly, then to investigate how to better clarify it.