Re: BUG #7572: virtualxid lock held by bgwriter on promoted slaves

On 26 September 2012 22:33, <daniele(dot)varrazzo(at)gmail(dot)com> wrote:
> The following bug has been logged on the website:
>
> Bug reference: 7572
> Logged by: Daniele Varrazzo
> Email address: daniele(dot)varrazzo(at)gmail(dot)com
> PostgreSQL version: 9.1.4
> Operating system: Linux
> Description:
>
> Hello,
>
> when a slave is promoted, the pgwriter keeps holding a lock with virtualxid
> "1/1" and virtualtransaction "-1/0". Such lock stops pg_reorg to run (as
> reported here:
> http://pgfoundry.org/tracker/index.php?func=detail&aid=1011203&group_id=1000411&atid=1376)
> but I've verified the same condition on 9.1.4).
>
> Is it possible to free that lock on slave promotion?
>
> Is it safe to ignore that lock for pg_reorg sake? The program is which is
> probably waiting for all the transactions to finish before swapping the
> table in the system catalog but I'm not sure about that yet.

This one is mine.... I don't think its important we hold that lock,
but will check.

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