From owner-freebsd-net@freebsd.org Mon Nov 7 15:46:20 2016 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id ACFE2C34B50 for ; Mon, 7 Nov 2016 15:46:20 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 82F8DA22 for ; Mon, 7 Nov 2016 15:46:20 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id uA7FkJ1o084917 for ; Mon, 7 Nov 2016 15:46:20 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-net@FreeBSD.org Subject: [Bug 208409] [PATCH] igb and ALTQ Date: Mon, 07 Nov 2016 15:46:20 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 10.3-BETA2 X-Bugzilla-Keywords: IntelNetworking, patch X-Bugzilla-Severity: Affects Many People X-Bugzilla-Who: ncrogers@gmail.com X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-net@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 07 Nov 2016 15:46:20 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D208409 ncrogers@gmail.com changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |ncrogers@gmail.com --- Comment #10 from ncrogers@gmail.com --- ALTQ has never worked with the multiqueue drivers. em(4) interfaces work "o= ut of the box" when ALTQ is included in the kernel, because the default em(4) behavior has multiqueue disabled. With igb(4) and ixgbe(4), you MUST enable= the legacy path in the driver. Prior to this patch, the only way to sensibly do this was to manually edit the driver and add an IGB_LEGACY_TX define. It sounds like there is an issue with the legacy single-queue path, perhaps only when ALTQ is not actually used in the PF configuration? FWIW I support many PF routers with igb(4) interfaces having ALTQ enabled (not just compil= ed in the kernel), including the IGB_LEGACY_TX path, and have not had any problems, albeit I am still running 10.1-RELEASE. This was a much-needed patch from the perspective of someone that supports = many PF+ALTQ installations and has had to add IGB_LEGACY_TX manually for years n= ow (since the 8.x days I believe). However it appears that there are many peop= le that have haphazardly added ALTQ support to their kernels without actually using it, and that is definitely not a case where you would want to downgra= de to the single-queue behavior. Somehow this patch in question made it through even though the issue has be= en brought up many times before over the past few years. At one point there was discussion of adding some kind of kernel tunable to enable the IGB/IXGBE le= gacy transmit paths, but it did not gain any committer support. Perhaps this is = the way to go as it would have prevented the problem where people are now unexpectedly running the single-queue transmit path because ALTQ is in their kernel. The following PR had discussed the kernel tunable option. https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D194197 --=20 You are receiving this mail because: You are the assignee for the bug.=