Date: Mon, 07 Nov 2016 15:46:20 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-net@FreeBSD.org Subject: [Bug 208409] [PATCH] igb and ALTQ Message-ID: <bug-208409-2472-2kHTIrSMtC@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-208409-2472@https.bugs.freebsd.org/bugzilla/> References: <bug-208409-2472@https.bugs.freebsd.org/bugzilla/>
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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.=
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