Hi all, We've got an 82599 device using the XAUI interface over an ATCA backplane data link, using version 2.0.72.4 of the ixgbe driver from sourceforge. (We also tried 2.1.4 and it didn't help.)
As I mentioned a while back, I'm investigating an issue where under load we eventually suddenly stop receiving packets. We're sending out packets, I can see the reply being sent with tcpdump on other hosts, but we never receive the reply. The driver doesn't complain about loss of carrier (and doesn't indicate dropped packets). I added some instrumentation that triggers once we haven't received any packets for at least 300ms (and I know that we should be receiving some). The instrumentation dumps the values of various interrupt-related registers on the 82599 and also walks the rx rings to see if there are any packets ready to process. Here's the result of a typical event: eth4 (affected device) EICS: 1 EIMS: d619fffe EIMC: d619fffe EIAC: 4000ffff EIAM: ffff packets waiting on rx ring 0 For comparison, here is what eth3 looks like. This device is also an 82599, part of the same bond link, but isn't showing any problems. EICS: 0 EIMS: d619ffff EIMC: d619ffff EIAC: 4000ffff EIAM: ffff no packets waiting on any rx rings Given the above, it appears that we're somehow getting into a state where the interrupts are automatically disabled but then the driver doesn't re-enable them right away. Eventually it does re-enable them, but we've seen it take up to 750ms for traffic to start flowing again. We've got a few clues--it seems to be related to tcp traffic, it doesn't take much traffic at all (less than 10% of a single core cpu usage), and dropping the link speed from 10Gbps to 1Gbps made the problem go away. Anyone got any ideas what might be going on? Chris PS The manual says that EICS and EIMC are both write-only, yet the driver reads both of them for the register dump and reads EICS for actual operation. Is this using undocumented behaviour? -- Chris Friesen Software Developer GENBAND chris.frie...@genband.com www.genband.com ------------------------------------------------------------------------------ Beautiful is writing same markup. Internet Explorer 9 supports standards for HTML5, CSS3, SVG 1.1, ECMAScript5, and DOM L2 & L3. Spend less time writing and rewriting code and more time creating great experiences on the web. Be a part of the beta today. http://p.sf.net/sfu/beautyoftheweb _______________________________________________ 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
