Re: [Qemu-devel] [PULL 00/57] Migration pull

[Peter Maydell]

On 9 November 2015 at 17:40, Dr. David Alan Gilbert <address@hidden> wrote:
> * Peter Maydell (address@hidden) wrote:
>> 57 patches three days before hard freeze? Are you *really* sure about this?
>
> Well:
>   a) It's been posted and tested for a long time now; most things seem happy.
>   b) It's been posted and reviewed multiple times, the changes since the
>      previous version are purely cleanups from previous review and one
>      fix.
>   c) We've been feeding some smaller parts in, individually, but a lot
>      of the changes are only used by later parts of the code base, and
>      people don't like changes going in that aren't used yet.
>   d) I'm here for those 3 days and after to fix it if it explodes.

I'm putting it through the merge process, but I really don't like
huge pulls hitting the tree very late in softfreeze. The idea of
softfreeze is supposed to be that we start out with a lot of churn
and gently drop down towards "no changes except bugfixes" as we hit
the hardfreeze date. Big changesets are more likely to be destabilizing,
and destabilizing changes are worse the later in the freeze process
they hit.

Also, by dropping a big pullrequest late you are significantly
increasing your risk that compile failures and other "only noticed
in the merge process" problems will take long enough to fix that
you fail to get the thing in before the hardfreeze deadline.
Any pull request of 50 patches or more can end up running into
several of that kind of problem and need several tries to get
through. (For instance, you've got a windows build failure, which
I'm about to send a separate mail for.)

thanks
-- PMM