Thanks for your reply. I learnt something again! On Fri, 22 Dec 2006, Alvaro Herrera wrote: > Date: Fri, 22 Dec 2006 17:25:43 -0300 > From: Alvaro Herrera <alvherre@xxxxxxxxxxxxxxxxx> > To: ohp@xxxxxxxxxx > Cc: Tom Lane <tgl@xxxxxxxxxxxxx>, > Kevin Grittner <Kevin.Grittner@xxxxxxxxxxxx>, > Jeremy Haile <jhaile@xxxxxxxxxxx>, pgsql-performance@xxxxxxxxxxxxxx > Subject: Re: [PERFORM] URGENT: Out of disk space pg_xlog > > ohp@xxxxxxxxxx wrote: > > On Fri, 22 Dec 2006, Tom Lane wrote: > > > > > Date: Fri, 22 Dec 2006 13:14:18 -0500 > > > From: Tom Lane <tgl@xxxxxxxxxxxxx> > > > To: Kevin Grittner <Kevin.Grittner@xxxxxxxxxxxx> > > > Cc: Jeremy Haile <jhaile@xxxxxxxxxxx>, pgsql-performance@xxxxxxxxxxxxxx > > > Subject: Re: [PERFORM] URGENT: Out of disk space pg_xlog > > > > > > "Kevin Grittner" <Kevin.Grittner@xxxxxxxxxxxx> writes: > > > > As I understand it, the log space accumulates for the oldest transaction > > > > which is still running, and all transactions which started after it. > > > > > > No, pg_xlog can be truncated as soon as a checkpoint occurs. > > > > Even for currently running transactions ? > > > > My understanding was that checkpoint was syncing data files for commited > > transactions. > > No, it syncs data files for all transactions, even those currently > running. > > > What happens to pg_xlogs when a transaction updates M of rows/tables and > > runs for hours? > > They get recycled as the update goes. > > -- Olivier PRENANT Tel: +33-5-61-50-97-00 (Work) 15, Chemin des Monges +33-5-61-50-97-01 (Fax) 31190 AUTERIVE +33-6-07-63-80-64 (GSM) FRANCE Email: ohp@xxxxxxxxxx ------------------------------------------------------------------------------ Make your life a dream, make your dream a reality. (St Exupery)
