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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam01 X-Stat-Signature: u7p8fugo8ck4s7gd5t9et5mxi8wrgo3b X-Rspam-User: X-Rspamd-Queue-Id: 9A324120011 X-HE-Tag: 1715085409-613392 X-HE-Meta: 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 ohnggBZm Hj9fpjAeR54aV+RC26yIJVDupHS1sX90Wt63kSgy0yKGpA13zwE2cd8NEH3mn1plzCoETxZFALu5XgoK86BOtgQXIs4tVsIFTHY0VtS57t62nlcojuOe1FQnLjgIlEaitffMMicInijvdopxDIb2eKd5CUWiSiHTX50a4w3NY423wYgE= 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 07/05/2024 12:42, David Hildenbrand wrote: > On 07.05.24 13:34, David Hildenbrand wrote: >> On 07.05.24 13:26, Ryan Roberts wrote: >>> On 07/05/2024 12:14, Ryan Roberts wrote: >>>> On 07/05/2024 12:13, David Hildenbrand wrote: >>>>> >>>>>> https://github.com/intel/lmbench/blob/master/src/lat_mem_rd.c#L95 >>>>>> >>>>>>> suggest. If you want to try something semi-randomly; it might be useful >>>>>>> to rule >>>>>>> out the arm64 contpte feature. I don't see how that would be interacting >>>>>>> here if >>>>>>> mTHP is disabled (is it?). But its new for 6.9 and arm64 only. Disable with >>>>>>> ARM64_CONTPTE (needs EXPERT) at compile time. >>>>>> I don't enabled mTHP, so it should be not related about ARM64_CONTPTE, >>>>>> but will have a try. >>>>> >>>>> cont-pte can get active if we're just lucky when allocating pages in the right >>>>> order, correct Ryan? >>>> >>>> No it shouldn't do; it requires the pages to be in the same folio. >> >> Ah, my memory comes back. That's also important for folio_pte_batch() to >> currently work as expected I think. We could change that, though, and >> let cont-pte batch across folios. > > Thinking about it (and trying to refresh my memories), access/dirty bits might > be why we don't want to do that. Yes correct; we only get a single access/dirty bit for the whole contpte block. So can't honour the core kernel's tracking requirements when the pages are not part of a single folio.