From mboxrd@z Thu Jan 1 00:00:00 1970 From: Or Gerlitz Subject: Re: [PATCH] mlx4: allow for 4K mtu configuration of IB ports Date: Thu, 26 May 2011 09:18:25 +0300 Message-ID: <4DDDF0B1.6090305@mellanox.com> References: <055701cc1b29$c8fcc6c0$5af65440$@systemfabricworks.com> 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: Roland Dreier , Jim Schutt Cc: Bob Pearson , Or Gerlitz , linux-rdma , Vladimir Sokolovsky , Alex Netes List-Id: linux-rdma@vger.kernel.org Roland Dreier wrote: > Bob Pearson wrote: >> With lash+mesh redsky required 6-7 VLs to wire up without deadlocks. I think >> that Jim's version uses 8 SLs but only 2VLs to work. >> If someone was using a torus and also wanted to support QOS and also wanted >> to separate multicast and management on a separate VL to be absolutely sure >> that there is no possibility of a deadlock you might end up with #QOS * 2 + >> 1 which would be 5 using the current algorithm. > But again you don't need all those VLs on the HCAs' links, do you? Jason Gunthorpe wrote: > Routing algorithms only need VLs on interswitch links, not on HCA to > switch links. The only use of the HCA to switch VLs is for QoS. Mesh > topologies can usually be routed with only two VLs, but you need alot > of SLs to make that work. Bob, Jim, Alex I wasn't sure if the SL-to-VL mapping done by open SM is dictated by the directives @ the user config file or if the routing algorithm is "VL aware" but the routing engine? if the latter, do interswitch links use different mapping vs. HCA - switch links? Or. -- 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