Re: [GSoC2014] Patch ALTER TABLE ... SET LOGGED

On Fri, Aug 22, 2014 at 2:32 PM, Alvaro Herrera
<alvherre(at)2ndquadrant(dot)com> wrote:
> Fabrízio de Royes Mello wrote:
>> Em sexta-feira, 22 de agosto de 2014, Alvaro Herrera <
>> alvherre(at)2ndquadrant(dot)com> escreveu:
>>
>> > Fabrízio de Royes Mello wrote:
>> >
>> > > I forgot to mention... I did again a lot of tests using different
>> > > replication scenarios to make sure all is ok:
>> > > - slaves async
>> > > - slaves sync
>> > > - cascade slaves
>> >
>> > On v13 you mean?
>> >
>> Exactly!
>
> Great. Pushed. Thanks for the patch.

Hmm. I confess to not having paid enough attention to this, but:

1. Loggedness is not a word. I think that "persistence" or
"relpersistence" would be better.

2. The patch seems to think that it can sometimes be safe to change
the relpersistence of an existing relation. Unless you can be sure
that no buffers can possibly be present in shared_buffers and nobody
will use an existing relcache entry to read a new one in, it's not,
because the buffers won't have the right BM_PERSISTENT marking. I'm
very nervous about the fact that this patch seems not to have touched
bufmgr.c, but maybe I'm missing something.

--
Robert Haas
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