On 02/19/2014 02:38 PM, John-Paul Robinson wrote: > On 02/17/2014 07:10 PM, Ben Greear wrote: >> First, check 'dmesg' and make sure your NICs are using at least >> x8 pci with 5GT/s. > > I checked dmesg and my system reports that the Intel card is on x8 pci > with 5GT/s. > >> >> Check BIOS and disable 'VT-d' if it is on...it hurts performance by >> 50% or so. > > I checked my bios and only have an option to enable "Virtualization > Support". My cpuinfo shows vmx is available and the documentation > states that VT-d is available on this processor but it's not clear how I > would selectively disable that feature through my bios. The system is a > Dell R620. > > I'm assuming VT-d is active. This system is targeted for KVM use so it > would be nice to have VT-d as an option though I plan to share my 10G > card across all virtual machines. It would be disappointing if the > Intel 520X performs poorly with VT-d on, especially if I can't turn it > off. :/
Well, VT-d kills our performance on bare metal, but maybe it will help if you are using virtual machines. If you use 'perf top' and see lots of CPU used in ixgbe, that usually means vt-d is enabled in my experience. Either way, the Intel guys would know more about this than I do, so I'll defer to them. Thanks, Ben -- Ben Greear <gree...@candelatech.com> Candela Technologies Inc http://www.candelatech.com ------------------------------------------------------------------------------ Managing the Performance of Cloud-Based Applications Take advantage of what the Cloud has to offer - Avoid Common Pitfalls. Read the Whitepaper. http://pubads.g.doubleclick.net/gampad/clk?id=121054471&iu=/4140/ostg.clktrk _______________________________________________ E1000-devel mailing list E1000-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/e1000-devel To learn more about Intel® Ethernet, visit http://communities.intel.com/community/wired
