Re: release slippage

On Thu, Jun 9, 2011 at 10:37 AM, Kevin Grittner
<Kevin(dot)Grittner(at)wicourts(dot)gov> wrote:
> There is this pending patch, without which there are infrequent
> conditions under which the users could get a LOG level message and
> accumulate files in pg_serial:
>
> http://archives.postgresql.org/message-id/4DEE7BE4020000250003E2BD@gw.wicourts.gov

That seems important to fix.

> The other pending patch relates to the false positives serialization
> failures and funny-looking pg_lock entries from not ignoring
> non-MVCC snapshots in SSI.  I don't think Dan had any problem with
> the patch I offered, but I wasn't sure what to do about two
> functions.  He researched that and proposed a way to handle those.
> That looked good to me on a first pass except that there was one
> line he left at NULL instead of plugging in the snapshot. That looks
> like an easily-fixed oversight.  It will take me about an hour to
> review his changes in detail and re-test everything, although I
> don't expect any other issues.  It seems odd not to include a change
> that was requested by Tom, Robert, and Heikki (and which Dan and I
> both put in the hours to have a patch before beta2) in beta2.  It
> does fix the issue which people were concerned about (the predicate
> locks acquired on the table heap by the transaction when doing a
> REINDEX within a serializable transaction is no longer occuring.)

I didn't realize I had requested to include this, but I've concluded
after looking over it that I'm not qualified to commit it. Based on a
quick IM session with Heikki I am doubtful he'll be able to get to it
before the wrap, but we'll see, I guess.

In any case, if this misses beta2, I'm not feeling like we'd need to
push beta3 just for that reason. I'm not even 100% convinced that it
needs to be in 9.1. We're talking about fixing a relatively rare
false positive from a system which by its design necessitates that
users be prepared for the possibility of false positives. If getting
this fix in is going to mean that we have to wait another month and
push another beta when that otherwise wouldn't be necessary, I'd vote
to ship what we have. But I doubt that's really the decision we have
to make anyway.

One other problem I'm realizing: didn't Peter ask Bruce to revert the
change to make pg_upgrade ignore case differences in locale names, on
the grounds that it was not safe?

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company