Re: CIC and deadlocks

From: "Simon Riggs" <simon(at)2ndquadrant(dot)com>
To: "Pavan Deolasee" <pavan(dot)deolasee(at)gmail(dot)com>
Cc: "PostgreSQL-development" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: CIC and deadlocks
Date: 2007-03-31 13:14:36
Message-ID: 1175346876.4386.877.camel@silverbirch.site
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-patches

On Sat, 2007-03-31 at 17:45 +0530, Pavan Deolasee wrote:
>
> Isn't CREATE INDEX CONCURRENTLY prone deadlock conditions ?
> I saw one with VACUUM today. But I think it can happen with other
> commands like VACUUM FULL, CLUSTER, CREATE INDEX
> CONCURRENTLY and so on. These commands conflict on the
> ShareUpdateExclusiveLock held by CIC and hence would wait for
> CIC to release the lock. At the same time, CIC would wait for these
> transactions to complete.
>
> We know that these commands are run in a separate transaction
> and do not do any index fetches or inserts/updates. So in principle
> CIC need not wait for these transactions to complete in any
> of its waits. May be we can skip waits on the transactions that
> are running one of these commands.

Yes, because I proposed it already. :-)

"utility transactions" in - Latest plans for Utilities with HOT

--
Simon Riggs
EnterpriseDB http://www.enterprisedb.com

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message korryd 2007-03-31 13:34:16 Re: Last minute mini-proposal (I know, I know) forPQexecf()
Previous Message Pavan Deolasee 2007-03-31 12:15:57 CIC and deadlocks

Browse pgsql-patches by date

  From Date Subject
Next Message Magnus Hagander 2007-03-31 14:09:18 Re: COPY-able sql log outputs
Previous Message Pavan Deolasee 2007-03-31 12:15:57 CIC and deadlocks