[LLVMdev] please stabilize the trunk

[Bill Wendling]

On Wed, Jul 15, 2009 at 1:50 PM, Dale Johannesen<dalej at apple.com> wrote:
>
> On Jul 15, 2009, at 1:43 PMPDT, Török Edwin wrote:
>> On 2009-07-15 23:24, Dale Johannesen wrote:
>>> On Jul 15, 2009, at 11:52 AMPDT, Stuart Hastings wrote:
>
>>> I wonder if we might be able to automate the stabilization somewhat.
>>> I'm not at all sure this can be done without introducing worse
>>> problems that it solves, but here's some discussion fodder:
>>>
>>> Have the buildbots (or, probably better, one Master Buildbot) do
>>> auto-
>>> reversion when they see a new failure.  They would need to be able to
>>> detect bogus failures, such as temporary inability to connect to the
>>> svn server.
>>>
>>> Have checkins go to a branch, and have the buildbots automove them
>>> into mainline only after passing regression checks on the branch.
>>>
>>> If the procedures go wrong I can easily imagine the tree getting into
>>> a state where nobody knows what's in it very quickly, so we need to
>>> be
>>> careful...
>>>
>>
>> I'm not too keen about seeing buildbots play with trunk ;)
>
> Nor am I; normally I'd be the last person to suggest something like
> this.  But in the last few days we've seen just how bad a job humans
> can do...
>
We would need a much much more sophisticated testing system before we
can do something automated with reverting patches. One unfortunate
side-effect of auto-reverting is that it could revert one patch that
has a fix for that patch in the pipeline. Leading to unnecessary churn
by the build bots.

The core problem, in my opinion, is that people *don't* pay attention
to the build bot failure messages that come along. This is as much a
systemic problem as it is a community problem. Community in that we
need to foster the submission of well-tested patches. Systemic because
this is not how people hacking on open source projects typically
develop projects.

I like Daniel's idea of throwing more machines at the problem. It's a
brute force method, but there you go.

-bw