Re: [RESEND PATCH] mm: align larger anonymous mappings on THP boundaries

From: Kefeng Wang
Date: Tue May 07 2024 - 09:56:50 EST




On 2024/5/7 19:13, 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.

After ARM64_CONTPTE disabled, memory read latency is similar with ARM64_CONTPTE enabled(default 6.9-rc7), still larger than align anon reverted.


cont-pte can get active if we're just lucky when allocating pages in the right order, correct Ryan?