Review: Syncing from testing a success?

[Scott Kitterman]

"Martin Pitt" <martin.pitt at ubuntu.com> wrote:

>Hello Ubuntu developers,
>
>In Lucid we have switched the default syncing source from Debian
>unstable to testing [1], to avoid getting only pieces of large transitions
>which we then need to untangle ourselves, and generally avoid
>importing major regressions which are held back from Debian testing
>through reported RC bugs.
>
>This comes at the cost of a bigger wave of new package versions in the
>next release, and with the increased cost of more manual sync requests
>from unstable.
>
>Usually we'd switch back to unstable for 10.10 (maverick), but now is
>a good time for a review how the syncing from testing actually worked
>in practice and whether we'll keep it for LTSes, all releases, or drop
>it again.
>
>I have my own gut feeling about this, but to get from that to a
>sensible general evaluation we need to collect the gut feelings and
>practical experience of a lot of our developers.
>
>So, in your opinion, did syncing from testing
>
> (1) help to avoid introducing larger breakage into Ubuntu (for the
>     domain you are usually watching)

For packages being actively worked in Ubuntu, I don't think it made a lot of difference. For the long tail of Universe packages,  I think it was a mixed blessing.  It seemed to me that NBS was much easier to deal with, but I also ran into more than a few packages that we didn't get updates for at all for reasons not relevant to Ubuntu (e.g. FTBFS on an arch we don't have).

> (2) meant a smaller or larger amount of review and sync requests

My feeling for Universe is I'm not sure yet.  I'm still finding things that need fixing. I have seen more need for +really version downgrades than I recall seeing before. 

> (3) made it easier or harder to merge with Debian and get changes
>     integrated back upstream

Generally I think it made merging harder since when I wanted to merge from Unstable, it needed a manual merge. It also made it harder to feedback changes sometimes since I found cases where Debian Unstable was very different than what I'd gotten from Testing in Ubuntu. 

> (4) made library transitions easier or harder

I think it made for fewer,easier transions, but a few really awkward ones.

> (5) anything else that caused or eased problems that you can think
>     of

For the next development cycle or two, Debian will be frozen for Squeeze release preparations.  I think we definitely do not want to sync from Testing again until after Squeeze is out.

My preference would be to sync from Unstable for all non-LTS releases. If we do sync from Testing again, we should have some better tools for automatically pulling some packages from Unstable (e.g. it came from Unstable and doesn't exist in Testing).

>In order to not bias the discussion, I'll send my own experience as a
>followup later on.
>
>Thank you in advance for your answers, and let's have an outstanding
>Lucid release!
>
Thanks for bringing it up.

Scott K