Re: Recovery Test Framework - Mailing list pgsql-hackers

On Mon, 2009-01-12 at 08:37 -0800, Joshua D. Drake wrote:
> On Mon, 2009-01-12 at 11:18 -0500, Tom Lane wrote:
> 
> > > My point is that what Simon currently has (and so what you tested) is
> > > different from what is going to be commited (note the "final" in what
> > > I wrote) and I suspect there will be a certain number of non
> > > negligible adjustments (see the last discussions between Simon and
> > > Heikki and I don't think Tom has taken a look at these patches yet).
> > 
> > The thing that's disturbing me is that (to judge by what I've been
> > seeing on the mailing list) there's been a steady stream of "non
> > negligible adjustments" for the past two months.  That's good from
> > the standpoint that problems are getting found and fixed, but it's
> > not giving me any warm fuzzies about the code being ready to go.
> 
> This is the same thing that makes me nervous. The feature appears to be
> "Under heavy development". As I understand the development model the
> heavy development is supposed to happen before commit fest.

That simply not true. 

So far there have been 15 resolved issues, shown on Wiki
2 correctness issues, critical if not resolvable, but easily done
1 trivial porting issue
1 minor issue related to disallowed read-write modes
1 minor refactoring
3 minor issues resolved to no action
6 bugs, all easily diagnosed and fixed

plus

1 major refactoring, that required significant examination of internals
to achieve, but has not changed anything that we now agree is
significant (that also was a discussion point). Much of the difficulty
caused because the design needs to be both correct and performant, which
I believe it is.

So far this patch has had much less refactoring than async commit, which
reached version > 22 before it was committed. 

There are 322 separate code chunks touching 69 files, with more than
9000 lines of code (>11000 including patch diffs). In percentage terms,
that's pretty good "code quality".

There are two main oustanding tasks, which will be complete over the
next couple of days.

* prepared transactions - left because I knew Heikki wanted to refactor
things in a way that would rip out any code written for that part

* usability issues related to how/when queries get cancelled. That came
out of discussion during review and was not an outstanding item before
deadline.

There have been no changes to the main mechanisms in the patch, nor in
the user interface related parts. To be honest we might reasonably have
expected *more* change to have taken place than has done.

Some dev might sound like heavy lifting, because the code often involves
the internal mechanics of the transaction system, but this is hardly
either my or Heikki's first foray into that section of code and we're
used to hitting problems and solving them.

Anyway, I'm actually going to turn off my email for a few days. Talking
won't get it done and that way I can pretend you're all sending me
positive waves (not to pick specifically on you Josh).

-- Simon Riggs           www.2ndQuadrant.comPostgreSQL Training, Services and Support