From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hal Rosenstock Subject: Re: Unable to Connect Using Active Speed 2.5 Gbps and Active Width of 1 Date: Mon, 28 Mar 2011 16:18:23 -0400 Message-ID: <4D90ED0F.8010101@dev.mellanox.co.il> References: <4D90D9A2.7000107@dev.mellanox.co.il> <4D90DF38.1060407@dev.mellanox.co.il> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alan Cook Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org On 3/28/2011 3:26 PM, Alan Cook wrote: > Hal Rosenstock writes: >> >> LinkWidthEnabled is 1X or 4X and not just 1X. That's because there's no >> force_link_width option in OpenSM so I think the width you set is >> getting overwritten much like the speed was earlier until you discovered >> force_link_speed 0. > > But I see LinkWidthActive set to 1X, which as I understood denoted the width > currently being used. Yes as long as a renegotiation occurred after the enabled width was changed. > If I set LinkWidthActive to 4X, I am able to transfer > just fine. > > Also, I do see LinkWidthEnabled being changed from "1X" to "1X or 4X" (most > likely by OpenSM as you suggest), but only after the link is up and active. If it's changed after the link is up and no renegotiation occurs, then this is a don't care as you indicate/ > I am able to transfer at 5 Gbps 1X and 10 Gbps 1X, just not 2.5 Gbps 1X. I don't have a theory for why only that combo would fail. Do you have any other HCA types to try ? >> >> Also, is this b2b HCAs or is there a switch in the topology ? >> > > It's b2b HCAs, no switch. I think ibportstate uses combine routing which is problematic if directed at HCA. -- 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