Re: per user/database connections limit again - Mailing list pgsql-patches

From Bruce Momjian
Subject Re: per user/database connections limit again
Date
Msg-id 200508011413.j71EDIK02857@candle.pha.pa.us
Whole thread Raw
In response to per user/database connections limit again  (Petr Jelinek <pjmodos@parba.cz>)
List pgsql-patches
An updated version of your patch has been applied and will be in 8.1.  Thanks.

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pgman wrote:
>
> I have "worked over" your patch and I think it is ready for application.
>
> I changed the syntax to CONNECTION LIMIT, which seems most natural.  We
> could skip CONNECTION and just use a LIMIT keyword, but that seems too
> terse.
>
> I removed your use of the pg_auth flat file.  By the time you have the
> PROC entry to do your lookups, you might as well just use the system
> cache.
>
> There is a race condition in the code because we set our PROC entry
> before we check for other entries.  If there is one connection left and
> two backends do this at the same time, they would both fail, while one
> should fail and the other succeed. Without a lock, I see no way to avoid
> it so I just commented it in the code.
>
> Also, I felt that zero should mean allow no/zero connections, rather
> than representing unlimited connections.  I used -1 for unlimited.  We
> can either document the use of -1, or add syntax to allow NO CONNECTION
> LIMIT, or something like that.
>
> The patch requires a catalog version update when applied.

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