Re: Hot Standby: Relation-specific deferred conflict resolution

Simon Riggs wrote:
> On Fri, 2010-01-29 at 08:26 +0200, Heikki Linnakangas wrote:
>> Simon Riggs wrote:
>>> Conflict resolution improvements are important to include in this
>>> release, as discussed many times. Proposal given here
>>> http://archives.postgresql.org/pgsql-hackers/2009-12/msg01175.php
>>> presents a viable design to improve this.
>>>
>>> Following patch is a complete working implementation of that design.
>>> I'm still testing it, but its worth publishing as early as possible to
>>> allow discussion. Not for commit, just yet, but soon.
>> Um, you're not considering this for 9.0, are you? I think it's time to
>> concentrate on the must-fix issues and fix the rough edges in what we have.
>
> Yes, it is important.
>
>> For example, the "can't start hot standby mode from a shutdown
>> checkpoint" issue is a must-fix issue in my opinion, about 10x as
>> important as this. When that was last discussed, many others agreed. I
>> run into that all the time when testing streaming replication, and every
>> time I go "Huh, why isn't the standby opening up for connections?", and
>> then, "Ahh, it's this stupid shutdown checkpoint issue again".
>
> That was not the feedback I have received. Nobody has commented on that
> to me,

Yes they have. I have on several occasions, as have other people on this
mailing list:

http://archives.postgresql.org/message-id/603c8f070912201611h4951087craa080ff6b48a97cd@mail.gmail.com
http://archives.postgresql.org/message-id/4B30AE53.6020202@gmail.com
http://archives.postgresql.org/message-id/407d949e0912220738je1e0141m87d7b688dd4ba27f@mail.gmail.com

I even *fixed* that already, but you decided to take it out before
committing. I then added it to the list of must-fix items in the TODO
list, but you took that out too. I have no objection to doing things in
smaller steps, but this *is* a must-fix item before release. I still
don't understand why you took it out, nor why you're objecting to that.

> though many have commented on the need for the current patch.

Who?

> As
> mentioned, I went to the trouble of running a meeting to gain additional
> feedback and the result was very clear.

So what was the clear result?

If you're looking for things to do, I agree with Greg Stark that the
removal of max_standby_delay=-1 option is not good. That should be fixed
too.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com