[dpdk-dev] [PATCH] doc: add sampling and mirroring in testpmd guide

[Ferruh Yigit]

On 3/31/2021 7:38 AM, Jiawei(Jonny) Wang wrote:
> Hi Ferruh,
> 
>> -----Original Message-----
>> From: Ferruh Yigit <ferruh.yigit at intel.com>
>> Sent: Friday, March 26, 2021 1:11 AM
>> To: Jiawei(Jonny) Wang <jiaweiw at nvidia.com>; Slava Ovsiienko
>> <viacheslavo at nvidia.com>; xiaoyun.li at intel.com; Ori Kam
>> <orika at nvidia.com>
>> Cc: dev at dpdk.org; Andrew Rybchenko <arybchenko at solarflare.com>; NBU-
>> Contact-Thomas Monjalon <thomas at monjalon.net>
>> Subject: Re: [PATCH] doc: add sampling and mirroring in testpmd guide
>>
>> On 3/9/2021 1:18 PM, Jiawei Wang wrote:
>>> Update documentation for sample action usage in testpmd and show the
>>> command line example.
>>>
>>
>> +1 to document this.
>>
>> Indeed for all testpmd flow update, it must be mandatory to update "Flow
>> rules management" section for it, Ori what do you think?
>>
>>> Signed-off-by: Jiawei Wang <jiaweiw at nvidia.com>
>>> Acked-by: Viacheslav Ovsiienko <viacheslavo at nvidia.com>
>>
>> <...>
>>
>>> +Sample Sampling/Mirroring rules
>>> +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> +
>>> +Sample/Mirroring rules can be set by the following commands
>>> +
>>> +NIC-RX Sampling rule, the matched ingress packets are duplicated and
>>> +sent to the queue 1, and each second packets are marked with 0x1234
>>> +and sent to queue 0.
>>> +
>>
>> Also each second packets duplicated to queue 1, isn't it, because of 'ratio 2'?
>>
> 
> Yes, 'ratio=2' means that 50% packet will be sampled.
> 

I thought 'sample' action also applies to the "queue index 1" but most probably 
it only applies to 'sample_actions', so original paragraph is correct, perhaps 
except the 'duplicated' detail, and my comment "each second packets duplicated 
to queue 1" is wrong.

Can you please confirm if below is correct:
Assume 10 packets are received, from 1 to 10, after below rule queue status will be:
Queue0: 2, 4, 6, 8, 10 [All marked with 0x1234, duplicated packets]
Queue1: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 [Original packets]


>>> +::
>>> +
>>> + testpmd> set sample_actions 0 mark id  0x1234 / queue index 0 / end
>>> + testpmd> flow create 0 ingress group 1 pattern eth / end actions
>>> +        sample ratio 2 index 0 / queue index 1 / end
>>> +
>>> +E-Switch Sampling rule, the matched ingress packets are duplicated
>>> +and sent to port id 2, and each second packets are sent to eswitch
>> manager.
>>> +
>>
>> what is 'E-Switch', or "eswitch manager", isn't the mirror rule generic?
> 
> Here E-Switch means 'transfer=1' in flow attribute,  I will remove it since the concept is for Mellanox HW.
>