Re: [dpdk-dev] [dpdk-techboard] DPDK ABI/API Stability

[Kevin Traynor <ktraynor@redhat.com>]

On 04/04/2019 11:54, Bruce Richardson wrote:
<snip>

>
> My thoughts on the matter are:
> 1. I think we really need to do work to start hiding more of our data
> structures - like what Stephen's latest RFC does. This hiding should reduce
> the scope for ABI breaks.
> 2. Once done, I think we should commit to having an ABI break only in the
> rarest of circumstances, and only with very large justification. I want us
> to get to the point where DPDK releases can immediately be picked up by all
> linux distros and rolled out because they are ABI compatible.
> 

Maybe techboard should explicitly approve ABI breaks and new APIs (or
APIs at transition from experimental to core). Just as a way to get more
eyeballs and scrutiny on them.

> I'm not sure I like the idea of planned ABI break releases - that strikes
> me as a plan where we end up with the same number of ABI breaks as before,
> just balled into one release.
> 
> Question for Kevin, Luca and others who look at distro-packaging: is it the
> case that each distro will only ship one version of DPDK, or is it possible
> that if we have ABI breaks, a distro will provide two copies of DPDK
> simultaneously, e.g. a 19.11 ABI version and a 20.11 ABI version?
> 

It would probably double validation and maintenance, so it would require
a lot of extra effort.

> 
> So, in short, I'm generally in favour of a zero-tolerance approach for DPDK
> ABI breaks, and having ABI breaks as a major event reserved only for
> massive rework changes, such as major mbuf changes, or new memory layout or
> similar.
> 
> Regards,
> /Bruce
>