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Howlett" , "Uladzislau Rezki" , To: "Elijah" References: <20250924193643.4001-1-git@elijahs.space> <73d7d53f-439b-44a9-98ca-0b1c8fbc1661@elijahs.space> <6e9c820f-070b-409e-ac25-af96b8b962c6@elijahs.space> In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: F2C5D80010 X-Stat-Signature: qd4q8zfz9zxmjz9iin7xciqbnkhbpysb X-HE-Tag: 1758824253-53197 X-HE-Meta: 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 gDKfX5YZ i2xmiiG6JgWuYiaxzeqzhdg6uzrWLq0OHVlu71seq5cbCuPvnczyjjhNeyaiX0P9i/pzJIty88wMwjOM4XuDeFu+bFQMD5hM0MDIRu2tITRUG5VTP9Ez61rtgy0eS0qHSBx4srXuimwXiO/2GxLXRQqZHrdSVp0lEDARhb9rQ8c86RejczIa0g/MwFeEBijIezmFSPDCZt5MYLHSzhauegxKNDV9wCpunCSIRqTkV5t0Bd5SjghU+i5C7PseK76RDbdyhfw/HMwuxCBYUkb05ybuVGclBQ4kCLoD0tAcC69rGVDgY6mVjGDF8KqqXGqbp44Yl5QvnK5CbkZS7tGvIAhK+bi4uPiNP5m2b 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 Thu Sep 25, 2025 at 8:15 PM CEST, Danilo Krummrich wrote: > On Thu Sep 25, 2025 at 8:05 PM CEST, Elijah wrote: >> On 9/25/2025 10:43 AM, Danilo Krummrich wrote: >> >> > Anyways, I'd also like to hear some more opinions, especially=20 >> regarding (4), as >> > mentioned. >> >> ok I just looked it over. I think (4) isn't really viable, the cache=20 >> pointer storage overhead is probably too much (in addition to some=20 >> complex issues). > > Probably, given that kmemcache is meant to be used when we have a lot of = (small) > allocations. > > However, I'd like to hear from the MM folks, if there may be options in t= he > existing infrastructure, or if it's really a dead end. > > What are the other complex issues you are referring to? > >> I don't really like having a macro (so (3) basically)=20 >> and I think there are issues with non-static caches, I don't know=20 >> specifically though. obviously (1) doesn't work. (2) is exactly what I= =20 >> was thinking specifically for rbtree. IMO the only useful options are=20 >> (2) and (3). I would say maybe implement (2) first and if you want=20 >> macro-generated ZST allocators they can wrap whatever that Box ends up= =20 >> being. > > I'm not sold on duplicating the Box code just yet. What issues are you re= ferring > to? Also, if we argue that (4) has a problem with scalability, then (2) has the problem as well.