Re: WAL consistency check facility

On Mon, Oct 31, 2016 at 9:31 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Fri, Oct 28, 2016 at 2:05 AM, Michael Paquier
> <michael(dot)paquier(at)gmail(dot)com> wrote:
>> And here we go. Here is a review as well as a large brush-up for this
>> patch. A couple of things:
>> - wal_consistency is using a list of RMGRs, at the cost of being
>> PGC_POSTMASTER. I'd suggest making it PGC_SUSER, and use a boolean (I
>> have been thinking hard about that, and still I don't see the point).
>> It is rather easy to for example default it to false, and enable it to
>> true to check if a certain code path is correctly exercised or not for
>> WAL consistency. Note that this simplification reduces the patch size
>> by 100~150 lines. I know, I know, I'd expect some complains about
>> that....
>
> I don't understand how you can fail to see the point of that. As you
> yourself said, this facility generates a ton of WAL. If you're
> focusing on one AM, why would you want to be forced to incur the
> overhead for every other AM? A good deal has been written about this
> upthread already, and just saying "I don't see the point" seems to be
> ignoring the explanations already given.

Hehe, I was expecting you to jump on those lines. While looking at the
patch I have simplified it first to focus on the core engine of the
thing. Adding back this code sounds fine to me as there is a wall of
contestation. I offer to do it myself if the effort is the problem.
--
Michael