[PATCH v11 0/4] Recycle mbufs from Tx queue into Rx queue

[Stephen Hemminger]

On Tue, 22 Aug 2023 15:27:06 +0800
Feifei Wang <feifei.wang2 at arm.com> wrote:

>   Currently, the transmit side frees the buffers into the lcore cache and
> the receive side allocates buffers from the lcore cache. The transmit
> side typically frees 32 buffers resulting in 32*8=256B of stores to
> lcore cache. The receive side allocates 32 buffers and stores them in
> the receive side software ring, resulting in 32*8=256B of stores and
> 256B of load from the lcore cache.
> 
> This patch proposes a mechanism to avoid freeing to/allocating from
> the lcore cache. i.e. the receive side will free the buffers from
> transmit side directly into its software ring. This will avoid the 256B
> of loads and stores introduced by the lcore cache. It also frees up the
> cache lines used by the lcore cache. And we can call this mode as mbufs
> recycle mode.

Isn't the recycle ring just another cache? Why is the lcore cache slower?
Could we fix the general case there?