Re: Weird NET_RX softirq behavior

2014-08-07 Thread Jisheng Zhang
On Thu, 7 Aug 2014 22:47:58 -0700 Eric Dumazet wrote: > On Fri, 2014-08-08 at 10:37 +0800, Jisheng Zhang wrote: > > nd and recive 7 packets so far, about 1400bytes. Seems small > > comparing with the CPU1 and CPU2 NET_RX softirq numbers, right? > > > > Any other possible case? > > Multicast loo

Re: Weird NET_RX softirq behavior

2014-08-07 Thread Eric Dumazet
On Fri, 2014-08-08 at 10:37 +0800, Jisheng Zhang wrote: > nd and recive 7 packets so far, about 1400bytes. Seems small > comparing with the CPU1 and CPU2 NET_RX softirq numbers, right? > > Any other possible case? Multicast loop. Check dev_loopback_xmit() and its callers. -- To unsubscribe from

Re: Weird NET_RX softirq behavior

2014-08-07 Thread Jisheng Zhang
Hi Dmitry, On Thu, 7 Aug 2014 07:18:13 -0700 Dmitry Popov wrote: > On Thu, 7 Aug 2014 17:10:50 +0800 > Jisheng Zhang wrote: > > > 2. only one netdev in the system: eth0. > > There should also be lo (loopback) at least. Yep, I forget that ;) > > > 4. But NET_RX seems abnormal > > ~ # cat /p

Re: Weird NET_RX softirq behavior

2014-08-07 Thread Dmitry Popov
On Thu, 7 Aug 2014 17:10:50 +0800 Jisheng Zhang wrote: > 2. only one netdev in the system: eth0. There should also be lo (loopback) at least. > 4. But NET_RX seems abnormal > ~ # cat /proc/softirqs > CPU0 CPU1 CPU2 CPU3 > NET_RX: 445587

Weird NET_RX softirq behavior

2014-08-07 Thread Jisheng Zhang
Hi list, I observed one weird NET_RX softirq behavior: 1. CONFIG_RPS=y in kernel config file. 2. only one netdev in the system: eth0. eth0 only has one interrupt which is all handled by CPU0. eth0 doesn't support RFS_ACCEL "cat /proc/interrupts" shows ~ # cat /