Re: [dpdk-dev] [PATCH v5] app/testpmd: add option ring-bind-lcpu to bind Q with CPU

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 1/25/2018 3:40 AM, Simon Guo wrote:
> 
> Hi Konstantin,
> On Thu, Jan 18, 2018 at 12:14:05PM +0000, Ananyev, Konstantin wrote:
>> Hi Simon,
>>
>>>
>>> Hi, Konstantin,
>>> On Tue, Jan 16, 2018 at 12:38:35PM +0000, Ananyev, Konstantin wrote:
>>>>
>>>>
>>>>> -----Original Message-----
>>>>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of wei.guo.simon@gmail.com
>>>>> Sent: Saturday, January 13, 2018 2:35 AM
>>>>> To: Lu, Wenzhuo <wenzhuo.lu@intel.com>
>>>>> Cc: dev@dpdk.org; Thomas Monjalon <thomas@monjalon.net>; Simon Guo <wei.guo.simon@gmail.com>
>>>>> Subject: [dpdk-dev] [PATCH v5] app/testpmd: add option ring-bind-lcpu to bind Q with CPU
>>>>>
>>>>> From: Simon Guo <wei.guo.simon@gmail.com>
>>>>>
>>>>> Currently the rx/tx queue is allocated from the buffer pool on socket of:
>>>>> - port's socket if --port-numa-config specified
>>>>> - or ring-numa-config setting per port
>>>>>
>>>>> All the above will "bind" queue to single socket per port configuration.
>>>>> But it can actually archieve better performance if one port's queue can
>>>>> be spread across multiple NUMA nodes, and the rx/tx queue is allocated
>>>>> per lcpu socket.
>>>>>
>>>>> This patch adds a new option "--ring-bind-lcpu"(no parameter).  With
>>>>> this, testpmd can utilize the PCI-e bus bandwidth on another NUMA
>>>>> nodes.
>>>>>
>>>>> When --port-numa-config or --ring-numa-config option is specified, this
>>>>> --ring-bind-lcpu option will be suppressed.
>>>>
>>>> Instead of introducing one more option - wouldn't it be better to
>>>> allow user manually to define flows and assign them to particular lcores?
>>>> Then the user will be able to create any FWD configuration he/she likes.
>>>> Something like:
>>>> lcore X add flow rxq N,Y txq M,Z
>>>>
>>>> Which would mean - on lcore X recv packets from port=N, rx_queue=Y,
>>>> and send them through port=M,tx_queue=Z.
>>> Thanks for the comment.
>>> Will it be a too compliated solution for user since it will need to define
>>> specifically for each lcore? We might have hundreds of lcores in current
>>> modern platforms.
>>
>> Why for all lcores?
>> Only for ones that will do packet forwarding.
>> Also if configuration becomes too complex(/big) to be done manually
>> user can write a script that will generate set of testpmd commands
>> to achieve desired layout.
> 
> It might not be an issue for skillful users, but it will be difficult
> for others.  --ring-bind-lcpu will help to simply this for them.

Discussion seems not concluded for this patch, and it is sting idle for more
than a year.

I am marking the patch as rejected, if it is still relevant please send a
new version on top of latest repo.

Sorry for any inconvenience caused.

For reference patch:
https://patches.dpdk.org/patch/33771/