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

[Luca Boccassi <bluca@debian.org>]

On Thu, 2019-04-04 at 14:05 +0100, Ray Kinsella wrote:
> > > 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?
> > 
> > We can ship multiple versions, although it's more work so there
> > should
> > be a good reason to do it. 
> 
> Well you already kind of do right.
> You ship 16.11.8 with Debian 9 and then 18.11 with Debian 9
> backports.

Yes indeed - backports has a different policy and is not part of
"Debian main" - for example, stability and security support are not
guaranteed. Also there is no guarantee of compatibility of co-
installability - while you can have the individual libraries from each
version at the same time, you can't have both libdpdk-dev packages
which are necessary to build an application. So you have to choose and
install either libdpdk-dev=16.11 or libdpdk-dev=18.11.

It is possible to have multiple versions in the same archive at the
same time, and with multiple -dev packages, and that's what I meant
when I mentioned it was more work.

> > At the moment in Debian and Ubuntu we don't,
> > and we tend to ship whatever the latest LTS version is at the
> > distro
> > freeze milestone - for example Debian 10 which will be released
> > soon
> > (TM) will have 18.11.0.
> 
> Presumably when 19.11 arrives, it will land in Debian 10 backports
> similarly.
> 
> I assume anything that lands in backports is not guaranteed to be ABI
> compatible with stable?

Yes, there's no guarantee.

-- 
Kind regards,
Luca Boccassi