[openib-general] IB CM and the case of the lost RTU: was a bunch of other topics...

[Or Gerlitz]

On 8/23/06, Sean Hefty <mshefty at ichips.intel.com> wrote:
> To recap (since it's been a couple of weeks), we have two general solutions for
> how to support the passive/server/target side of a connection:
>
> 1. One method requires that the passive side queue send WRs until they get a
> connection establish event.
>
> 2. An alternative allows sending immediately after receiving a response, but may
> require the user to manually transition the connection to established.  Failure
> to do so will cause the connection to tear down if the RTU is never received
> (even after retries).

The Voltaire iSER target implementation follows a variant of the first
method, namely it defers RX processing till getting a connection
established event.

This is ensured in the current product by the Gen1 Voltaire CM riding
on the the IB comm_established async event and synthesizing an RTU and
would be the same in the iser target we code over the Gen2 stack (CMA)
if the first method is implemented.

As typically there is some ULP level handshake when a connection
starts, there would be very little to queue (eg in iSER its the
login-request).

Or.