From: Edward Cree <ecree.xil...@gmail.com> Date: Tue, 12 Jan 2021 09:54:04 +0000
> Without wishing to weigh in on whether this caching is a good idea... Well, we already have a cache to bulk flush "consumed" skbs, although kmem_cache_free() is generally lighter than kmem_cache_alloc(), and a page frag cache to allocate skb->head that is also bulking the operations, since it contains a (compound) page with the size of min(SZ_32K, PAGE_SIZE). If they wouldn't give any visible boosts, I think they wouldn't hit mainline. > Wouldn't it be simpler, rather than having two separate "alloc" and "flush" > caches, to have a single larger cache, such that whenever it becomes full > we bulk flush the top half, and when it's empty we bulk alloc the bottom > half? That should mean fewer branches, fewer instructions etc. than > having to decide which cache to act upon every time. I though about a unified cache, but couldn't decide whether to flush or to allocate heads and how much to process. Your suggestion answers these questions and generally seems great. I'll try that one, thanks! > -ed Al
