Re: PG 12 draft release notes

On 5/22/19 4:26 PM, Michael Paquier wrote:
> On Wed, May 22, 2019 at 09:19:53AM +0900, Ian Barwick wrote:
>> the last two items are performance improvements not related to authentication;
>> presumably the VACUUM item would be better off in the "Utility Commands"
>> section and the TRUNCATE item in "General Performance"?
>
> I agree with removing them from authentication, but these are not
> performance-related items. Instead I think that "Utility commands" is
> a place where they can live better.
>
> I am wondering if we should insist on the DOS attacks on a server, as
> non-authorized users are basically able to block any tables, and
> authorization is only a part of it, one of the worst parts
> actually... Anyway, I think that "This prevents unauthorized locking
> delays." does not provide enough details. What about reusing the
> first paragraph of the commits? Here is an idea:
> "A caller of TRUNCATE/VACUUM/ANALYZE could previously queue for an
> access exclusive lock on a relation it may not have permission to
> truncate/vacuum/analyze, potentially interfering with users authorized
> to work on it. This could prevent users from accessing some relations
> they have access to, in some cases preventing authentication if a
> critical catalog relation was blocked."

Ah, if that's the intent behind/use for those changes (I haven't looked at them
in any detail, was just scanning the release notes) then it certainly needs some
explanation along those lines.

Regards

Ian Barwick

--
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