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charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2023-01-25 at 14:01 +0100, Michal Hocko wrote: >=20 > I have read through your cover letter and it talks about the > interface > but it doesn't really talk about usecases and how they are supposed > to > use this feature - except the prctl based flag gets inherited. So > could > you elaborate some more about those usecases please? I can explain a little about the use case. There are people who use forked (rather than threaded) servers for certain workloads, from a garbage collected language without pointers, which means madvise simply cannot be made available in that language. The people running that workload have experimented with uKSM in the past, and seen about a 20% capacity increase from doing that. Because madvise is not possible in that programming language, and the addresses of data keep moving around as things get garbage collected, KSM sharing needs to be enabled "from the outside" for that workload. prctl seems like a good way to do that. --=20 All Rights Reversed. --=-fHtooTLBHokjrlt3AOkT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEKR73pCCtJ5Xj3yADznnekoTE3oMFAmPReD0ACgkQznnekoTE 3oOf6Qf+OZdpabz5qPJU/62BiPgM4Iz1Ih3vwmzqU4gPC6zRlgHsqxQ9unGulcc5 u9IIstoDUDaZRtbvJas1YO3wlaBgyIag+J0yR0Vflg6KWnBrYz+AKa0f8rfi4I0H MPavada+vlPdaIM/duOza4Je/nUkKenXaknZ3ng/j17JfWTPDNbtF/0Qne0t4nnf pM0i49ZgGNPAAqeT6FI1jf07BN+01QVjDKellwxGx5s8MjNKkEsmvpXT2ePTJQhK YXhsdf1sP3C9ftRKOBBzp0izIjvwnSuKcauOdhckdmX69SLbVSgxUgaTVxBUa2Ur RUUcMqJMaSgPERS3K+TdPHAaIJYY8Q== =k7TU -----END PGP SIGNATURE----- --=-fHtooTLBHokjrlt3AOkT--