Re: [PATCH] io_uring: One wqe per wq

From: Jens Axboe
Date: Fri Mar 10 2023 - 15:38:30 EST


On 3/10/23 1:11 PM, Breno Leitao wrote:
> Right now io_wq allocates one io_wqe per NUMA node. As io_wq is now
> bound to a task, the task basically uses only the NUMA local io_wqe, and
> almost never changes NUMA nodes, thus, the other wqes are mostly
> unused.

What if the task gets migrated to a different node? Unless the task
is pinned to a node/cpumask that is local to that node, it will move
around freely.

I'm not a huge fan of the per-node setup, but I think the reasonings
given in this patch are a bit too vague and we need to go a bit
deeper on what a better setup would look like.

--
Jens Axboe