Re: Exclusive lock for database rename

On 2005-11-03, Peter Eisentraut <peter_e@gmx.net> wrote:
> Peter Eisentraut wrote:
>> Someone wanted to rename a database while someone else was running a
>> rather long pg_dump, so the rename had to wait, and everyone else had
>> to wait for the rename because no new connections would be allowed.
>
> As an auxiliary issue, why do the new connections have to wait in this
> case?  The rename waits for the AccessShareLock of the dump to be
> released, but meanwhile new connections should be able to get
> AccessShareLocks of their own.

No. New AccessShare locks block behind the pending AccessExclusive lock.
Otherwise AccessShare locks could starve the exclusive lock forever.

-- 
Andrew, Supernews
http://www.supernews.com - individual and corporate NNTP services