Re: [dpdk-dev] [dpdk-techboard] [RFC] Proposals and notes from ABI stability panel @ DPDK Userspace

[Kevin Traynor <ktraynor@redhat.com>]

On 25/09/2019 15:40, Bruce Richardson wrote:
> On Wed, Sep 25, 2019 at 03:29:16PM +0100, Ray Kinsella wrote:
>>
>>> In the short term, based on the feedback at the conference and to give
>>> something concrete to be considered, here is a suggestion,
>>>
>>> ABI freeze starts at 20.02 for 9 months, with a review as planned to see
>>> if 20.11 should be frozen 2 years.
>>>
>>> pros:
>>> + Eliminates any need for delaying 19.11 release
>>>
>>> + Allows maintainers to stick to current deprecation policy if they need
>>> to make changes prior to freeze (Based on comment from Hemmant)
>>>
>>> + Not sure if it's worthy of a new bullet or clear from above but I
>>> would add that changing the release cycle/deprecation policy etc 2 weeks
>>> (I think) before RC1 is late to say the least and there is no notice to
>>> users
>>>
>>> + Means that any changes required prior to freeze are not rushed with
>>> usual big LTS release (19.11). Gives more time and maybe during a saner
>>> release cycle (20.02)
>>>
>>> cons:
>>> - With view for possible 20.11 freeze, gives 2 releases to tease out
>>> process instead of 3
>>>
>>> - Perhaps it is desirable for some users to have the 19.11 LTS ABI
>>> compatible with 20.02/05/08 releases
>>>
>>> I've tried to keep them objective, of course people will have different
>>> opinions about starting a freeze now vs. later etc. too.
>>>
>>> thanks,
>>> Kevin.
>>>
>>
>> *interesting*
>>
>> Another approach, possibly better approach, is to see the LTS as the
>> final act following an ABI declaration/freeze.
>>
>> We we declare the v20 ABI in DPDK 20.02, and hold that ABI until 21.02
>> including the v20.11 LTS. The LTS then becomes the cumulation of the ABI
>> freeze.
>>
>> I didn't go this road, because of the community habit of pushing things
>> in just before the LTS, I thought it would be a bridge too far, and that
>> it would get considerable push back.
> 
> I actually think this approach was initially rejected as having an ABI
> break immediately after an LTS makes backporting fixes to the LTS more
> problematic.
> 

Yeah, it likely would. I guess the freeze cycle or end date of the
freeze trial (if i can call it that) could be discussed further later,
but the start date is the more immediate issue now.

> /Bruce
>