From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: InfiniBand HCA loopback on a single host (subnet manager needed?) Date: Wed, 9 Mar 2011 10:30:05 -0700 Message-ID: <20110309173005.GN22729@obsidianresearch.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Konstantin Boyanov Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org On Wed, Mar 09, 2011 at 09:04:39AM +0100, Konstantin Boyanov wrote: > I think this is achievable on a single host by using the loopback > capabilities of the InfiniBand HCA. The problem is, that I was not > able to find a comprehensive description of how one sets up such > loopback operation on the HCA chip. To enable loopback I'm pretty sure you need an IB link on the card, and a running SM to set the link the ACTIVE. Also, be aware that in my experience loopback is a special case on IB cards and the performance is not good, so testing in this manner may not be valid. If you have a dual port card you'd be better off connecting the ports together and doing your test from port 1 to port 2. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html