Re: [PATCH 1/1] xprtrdma: Post small RPC Calls inline

[Andrei-Alexandru Bleortu <me@andrei-z.com>]

On Thu, Oct 15, 2026, Chuck Lever wrote:
> These mean completion latency gains are noise compared to the client's
> own RPC tasking machinery. Perhaps the additional code complexity is
> not worth it yet.

Thanks for looking. The gain is real but small. Over 40 paired runs
its interval excludes zero, and a comment-only patch moved the result
by -0.0139 us. But the 4 KiB write took 48.4 us on average, so the Call
saves 0.4 % of it, and 0.8 % of the 35.7 us read.

> General policy is not to put device-specific details like this
> in ULP code. So, NACK on holding these numbers in a table in
> the rpcrdma.ko module.

Understood. Bart asked for the same on the SRP patch, and I proposed
the create flag you describe on linux-rdma:
https://lore.kernel.org/all/20261015212227.3338582-1-me@andrei-z.com/

I will drop this patch and the svcrdma one for now. If the flag goes
in, the client change shrinks to setting the flag and the check in the
send path, with your lower bound. You can judge then whether it is
worth it.