Re: Insufficient locking for ALTER DEFAULT PRIVILEGES

On Sun, Jun 21, 2015 at 11:11 AM, Andres Freund <andres@anarazel.de> wrote:
> On 2015-06-21 11:45:24 -0300, Alvaro Herrera wrote:
>> Alvaro Herrera wrote:
>> > Now that I actually check with a non-relation object, I see pretty much
>> > the same error.  So probably if instead of some narrow bug fix what we
>> > need is some general solution for all object types.  I know this has
>> > been discussed a number of times ...  Anyway I see now that we should
>> > not consider this a backpatchable bug fix, and I'm not doing the coding
>> > either, at least not now.
>>
>> Discussed this with a couple of 2ndQ colleagues and it became evident
>> that MVCC catalog scans probably make this problem much more prominent.
>> So historical branches are not affected all that much, but it's a real
>> issue on 9.4+.
>
> Hm. I don't see how those would make a marked difference. The snapshot
> for catalogs scan are taken afresh for each scan (unless
> cached). There'll probably be some difference, but it'll be small.

Yeah, I think the same.  If those changes introduced a problem we
didn't have before, I'd like to see a reproducible test case.

-- 
Robert Haas
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