Subject: Re: [RFC net-next] net: page_pool: cap alloc cache size and refill by pool ring size

From: Jakub Kicinski <[email-masked]>
Date: Tue, 24 Feb 2026 15:39:59 -0800

On Mon, 23 Feb 2026 11:24:10 +0200 Nimrod Oren wrote:
> I'd appreciate feedback on:
> * Whether this per-pool cache capping approach makes sense
> * If so, which option is preferable
> * Any alternative suggestions to better cap/scale the page_pool cache
>   parameters for large pages

I'd simply change the defines based on PAGE_SIZE. The allocation batch
size has nothing to do with the ring size, it's just amortizing
allocations within a single NAPI cycle.

#if PAGE_SIZE >= 64K
#define PP_ALLOC_CACHE_REFILL	16
#elif PAGE_SIZE >= 16K
#define PP_ALLOC_CACHE_REFILL	32
#else
#define PP_ALLOC_CACHE_REFILL	64
#endif

#define PP_ALLOC_CACHE_SIZE	(PP_ALLOC_CACHE_REFILL * 2)