Re: [HACKERS] [BUGS] Concurrent ALTER SEQUENCE RESTART Regression

On 5/10/17 12:24, Andres Freund wrote:
> The issue isn't the strength, but that we currently have this weird
> hackery around open_share_lock():
> /*
>  * Open the sequence and acquire AccessShareLock if needed
>  *
>  * If we haven't touched the sequence already in this transaction,
>  * we need to acquire AccessShareLock.  We arrange for the lock to
>  * be owned by the top transaction, so that we don't need to do it
>  * more than once per xact.
>  */
> 
> This'd probably need to be removed, as we'd otherwise would get very
> weird semantics around aborted subxacts.

Can you explain in more detail what you mean by this?

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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