On 02/03/2014 08:59 AM, Maksim M wrote: > Hi, Alexander > ------------------------------------------------------------------------ > > > Recently, I came across some issue with ixgbe drive. > The matter is following: > IXGBE is working in NAPI , so I was sure that Rx interrupt was fired for > first packet in the batch and after that, it works in polling mode(as > every tutorial explains). That first interrupt delegates the job via > napi_schedule() to the sofrirq to make polling. But as turned out, > interrupts is coming without being dependent whether traffic exist or > not. Polling method is constantly being called by softirq when cpu is > idle. Trying to debug the issue I see that interrupt is called every > time even there are no packets(interface is up but no physical > connection). I tried to check EICR, and the bit responsible for > particular queue is constantly high. I could not understand what causes > rx/tx interrupts. Tried to play with throttle rate(EITR), but even it is > set to zero it still fires interrupt. > > P.S > Sorry to bother and thanks in advance. > > Regards, Maksim
Maksim, In order to guarantee the interrupts continue to fire, even in the case of a dropped interrupt the service event handler also triggers an interrupt every 2 seconds in addition to checking for a hung Tx ring. If you check there should be code writing to the EICS register in the service tast that is triggering the interrupts you are seeing. Thanks, Alex ------------------------------------------------------------------------------ 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=121051231&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
