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Subject: Re: [RESEND PATCH] mm: align larger anonymous mappings on THP
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To: David Hildenbrand <david@redhat.com>,
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From: Ryan Roberts <ryan.roberts@arm.com>
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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.