Re: 3.4.1 and 3.5-rc1 Packet lost at 250Mb/s

["Nieścierowicz Adam" <adam.niescierowicz@justnet.pl>]

W dniu 06.07.2012 12:13, Eric Dumazet napisał(a):

> On Fri, 2012-07-06 at 11:47 +0200, Nieścierowicz Adam wrote:
>
>> Hello, Can I send something that will help determine the cause of 
>> the
>> problem? W dniu 08.06.2012 11:41, Eric Dumazet napisał(a):
>>
>>> On Fri, 2012-06-08 at 10:58 +0200, Nieścierowicz Adam wrote:
>>>
>>>> Hello, recently we changed on the router kernel from 2.6.38.1 to
>>>> 3.4.1 and noticed 30% packet loss when traffic increases up to
>>>> 250MB / s. Similar is for kernel 3.5-rc1 Here a link to ifstat
>>>> http://wklej.org/id/767577/ [1] [2]
>>> You should give as much as possible delails on your setup 
>>> (hardware,
>>> software) lspci cat /proc/cpuinfo cat /proc/interrupts ifconfig -a 
>>> tc
>>> -s -d qdisc dmesg netstat -s
>> currently running on 2.6.38.1 and traffic is 100Mb / s lspci:
>> http://wklej.org/id/769102/ [2] /proc/cpuinfo:
>> http://wklej.org/id/769104/ [3] /proc/interrupts:
>> http://wklej.org/id/769106/ [4] ifconfig -a:
>> http://wklej.org/id/769108/ [5] tc -s -d qdisc:
>> http://wklej.org/id/769109/ [6] dmesg: here are some logs from 
>> iptables
>> netstat -s: http://wklej.org/id/769110/ [7] lsmod:
>> http://wklej.org/id/769117/ [8] /proc/net/softnet_stat:
>> http://wklej.org/id/769116/ [9]
>
> Same infos of 3.5-rcX kernel would be nice.
>
> What NIC is eth0 ? (dmesg please)
>
> It seems all network traffic on 2.6.38 is handled by a single cpu 
> (cpu0)
>
> (seen in /proc/interrupts)
>
> I suspect that with 3.4 or 3.5 kernels, traffic is handled by many 
> cpus
> and they hit false sharing and contention.
>
> You probably get better performance doing some affinity tuning :
>
> For example,
> eth0 serviced by cpu0
> eth2 serviced by cpu1
> eth3 serviced by cpu2
> eth5 serviced by cpu3
>
> and so on...
>
> check and/or set /proc/irq/${NUM}/smp_affinity

hello
I would go back to an earlier thread.

Currently is installed kernel 3.6.0 and symptoms are the same

about configuration:

- affinity on

- lspci: http://wklej.org/id/843156/ [10]

- /proc/cpuinfo: http://wklej.org/id/843158/ [11]

- /proc/interrupts: http://wklej.org/id/843161/ [12]

- ifconfig -a: http://wklej.org/id/843162/ [13]

- tc -s -d qdisc: http://wklej.org/id/843164/ [14]

- dmesg: http://wklej.org/id/843166/ [15]

- lsmod: http://wklej.org/id/843167/ [16]

- /proc/net/softnet_stat: /proc/net/softnet_stat

attach something else?

Thanks