[openib-general] Re: Re: [PATCH] [RFC] - example user mode rdmaping/pongprogram using CMA

[Michael S. Tsirkin]

Quoting r. Steve Wise <swise at opengridcomputing.com>:
> Subject: Re: Re: [PATCH] [RFC] - example user mode rdmaping/pongprogram using CMA
> 
> > Hey Michael,
> > 
> > There is at most only one SEND in flight.  This is a test program, not a
> > performance program.  Its goal is to utilize SEND, RECV, RDMA READ, and
> > RDMA WRITE as well as CMA to setup the connection...
> > 
> > Thanks,
> > 
> > Steve.
> 
> By the way, in case its not clear:  The SEND/RECV exchanges are done
> just to advertise source and sink memory regions, and to indicate
> completion of rdma read and write operations to the peer.  The
> "ping/pong" data is transferred with rdma read and write operations.
> 
> Thanks for the feedback!
> 

Code tends to get copied around ... its easy to imagine someone
copying this and measuring the send latency. Just posting many WRs
in the initialization sequence, with no other code changes,
will fix this problem.

-- 
Michael S. Tsirkin
Staff Engineer, Mellanox Technologies