On Tue, 2010-01-26 at 19:07 -0500, Kelvin Ku wrote: > We recently purchased our first Nehalem-based system with a single Xeon E5530 > CPU. We were unable to boot FC6 on it and are trying to upgrade our network to > F11/F12 anyway, so we installed F11 on it. > > Our existing hardware includes Xeon 5100- and 5400-series CPUs running mainly > FC6 (2.6.22), except for a single Xeon 5150 system running F11. Our target > application consumes multicast data during business hours and has been dropping > packets more frequently on the new hardware/OS combination than on our older > systems. I've tried using the on-board Intel 82574L dual-port NIC (e1000e > driver) and a discrete Intel 82576 dual-port NIC (igb driver). Counters for the > NIC, socket layer, and switch don't show any dropped packets. > > My question is this: has anyone experienced performance degradation running a > UDP-consuming application after moving to a Nehalem-based system? We have yet > to identify whether the culprit is the hardware, the OS, or the combination of > the two. However, note that our app works fine on the 5150 system running F11 > that I mentioned above. > > Likewise, if you've migrated such an app to a Nehalem system and had to make > adjustments to get it to work as before, I'd like to hear from you too. > > Thanks, > Kelvin Ku Please post the output of: $ cat /proc/interrupts | grep eth $ ethtool -S ethX Which board are you using? Have you enabled hyper-threading? Have you disabled IO vt-d? In which slot did you installed the igb card? Have you tried enabling pci=msi in your kernel's command line? Per your question, at least when dealing with packets from within the kernel, a Nehalem box is fully capable of handling >20Gbps (depending on the packet size) - so I doubt that this is a hardware issue. - Gilboa -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
