> -----Original Message-----
> From: Ferruh Yigit <ferruh.yi...@amd.com>
> Sent: Friday, March 8, 2024 7:24 PM
> To: Brandes, Shai <shaib...@amazon.com>
> Cc: dev@dpdk.org
> Subject: RE: [EXTERNAL] [PATCH v3 07/33] net/ena: restructure the llq policy
> setting process
>
> CAUTION: This email originated from outside of the organization. Do not click
> links or open attachments unless you can confirm the sender and know the
> content is safe.
>
>
>
> On 3/6/2024 12:24 PM, shaib...@amazon.com wrote:
> > From: Shai Brandes <shaib...@amazon.com>
> >
> > The driver will set the size of the LLQ header size according to the
> > recommendation from the device.
> > Replaced `enable_llq` and `large_llq_hdr` devargs with a new devarg
> > `llq_policy` that accepts the following values:
> > 0 - Disable LLQ.
> > Use with extreme caution as it leads to a huge performance
> > degradation on AWS instances from 6th generation onwards.
> > 1 - Accept device recommended LLQ policy (Default).
> > Device can recommend normal or large LLQ policy.
> > 2 - Enforce normal LLQ policy.
> > 3 - Enforce large LLQ policy.
> > Required for packets with header that exceed 96 bytes on
> > AWS instances prior to 5th generation.
> >
>
> We had similar discussion before, although dev_args is not part of the ABI, it
> is an user interface, and changes in the devargs will impact users directly.
>
> What would you think to either keep backward compatilibity in the devargs
> (like not remove old one but add new one), or do this change in
> 24.11 release?
[Brandes, Shai] understood.
The new devarg replaced the old ones and added option to enforce normal-llq
mode which is critical for our release.
As you suggested, we will keep backward compatibility and add an additional
devarg for enforcing normal-llq policy.
That way, we can easily replace it in future releases with a common devarg
without the need to make major logic changes.
