Re: [PATCH v7] rps: Receive Packet Steering

[Changli Gao <xiaosuo@gmail.com>]

On Thu, Mar 18, 2010 at 7:50 AM, Tom Herbert <therbert@google.com> wrote:
>
>>>
>>> # echo "0 1 0 1 0 1 1 1 1 1" >/sys/class/net/eth0/queues/rx-0/rps_map
>>> # cat /sys/class/net/eth0/queues/rx-0/rps_cpus
>>> 3
>>> # cat /sys/class/net/eth0/queues/rx-0/rps_map
>>> 0 1 0 1 0 1 1 1 1 1
>>> # echo 3 >/sys/class/net/eth0/queues/rx-0/rps_cpus
>>> # cat /sys/class/net/eth0/queues/rx-0/rps_map
>>> 0 1
>>
>> Alternatively, the rps_map could be specified explicitly, which will
>> allow weighting.  For example "0 0 0 0 2 10 10 10"  would select CPUs
>> 0, 2, 10 for the map with weights four, one, and three respectively.
>> This would go back to have sysfs files with multiple values in them,
>> so it might not be the right interface.
>
> Here is a patch for this...
>
> Allow specification of CPUs in rps to be done with a vector instead of a bit map.  This allows relative weighting of CPUs in the map by repeating ones to give higher weight.
>
> For example "echo 0 0 0 3 4 4 4 4 > /sys/class/net/eth0/queues/rx-0/rps_cpus"
>
> assigns CPUs 0, 3, and 4 to the RPS mask with relative weights 3, 1, and 4 respectively.
>

If the weight of CPU0 is 100, I have to repeat 0 100 times. How about
using the * to simplify the weight.

The above examples will be "echo 0*3 3 4*4 >
/sys/class/net/eth0/queues/rx-0/rps_cpus"

-- 
Regards，
Changli Gao(xiaosuo@gmail.com)