On 04/18/2018 05:31 AM, Sowmini Varadhan wrote:

I went through the patch set and the code looks fine- it extends existing
infra for TCP/GSO to UDP.

One thing that was not clear to me about the API: shouldn't UDP_SEGMENT
just be automatically determined in the stack from the pmtu? Whats
the motivation for the socket option for this? also AIUI this can be
either a per-socket or a per-packet option?

However, I share Sridhar's concerns about the very fundamental change
to UDP message boundary semantics here.  

There is no change at all.

This will only be used as a mechanism to send X packets of same size.

So instead of X system calls , one system call.

One traversal of some expensive part of the host stack.

The content on the wire should be the same.