Re: [PATCH RFC 0/5] xprtrdma Send completion batching

Jason Gunthorpe
2017-09-06T19:39:46Z

On Wed, Sep 06, 2017 at 02:33:50PM -0400, Chuck Lever wrote:

> B. Force RPC completion to wait for Send completion, which
> would allow the post-v4.6 scatter-gather code to work
> safely. This would need some guarantee that Sends will
> always complete in a short period.

Why is waiting for the send completion so fundamentally different from
waiting for the remote RPC reply?

I would say that 99% of time the send completion and RPC reply
completion will occure approximately concurrently.

eg It is quite likely the RPC reply SEND carries an embeded ack
for the requesting SEND..

Jason