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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: CC2F51A0005 X-Stat-Signature: cskgqme5mwhp1maoxncoismajki6ogr3 X-HE-Tag: 1779776854-686028 X-HE-Meta: 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 v04jflvs 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, May 25, 2026 at 12:35:56PM +0300, Mike Rapoport wrote: > > This does, but it still fails to explain why kmalloc performs just as > > well as __get_free_page(s) these days. > > I don't think that in this case - a single allocation on the cold path - > the performance difference is even measurable. Well, please state that. > Nevertheless allocations from slab caches are way faster than > __get_free_page() (i.e. alloc_pages()) as it's essentially lockless > cmpxchg. Allocations that need to refill the cache do alloc_pages() with a > little of slab bookkeeping overhead. Please state that too.