[Pgcluster-general] PgCluster and concurrency

[mitani at sraw.co.jp]

Hi,

Would you try to set 'false' to 'auto_lock_table' in postgresql.conf.
And I recommend to use evincive transaction (BEGIN ... END ).

Regards,
----------
At.Mitnai


-- original message --
From: Lia Domide<lia.domide at codemart.ro>
To: <pgcluster-general at pgfoundry.org>
Sent: Tue, 22 Apr 2008 10:52:00 +0300
Subject: [Pgcluster-general] PgCluster and concurrency

>Hello guys,
>
> 
>
>How pgCluster does handle concurrent DB request?
>
> 
>
>Let us consider the following architecture, with at least 2 DB services: 
>
>LB
>
>DB1   DB2
>
>REP
>
>I need to execute multiple concurrent INSERT operations in the same table. 
>
>INSERT ROW1 goes LB --> DB1 -->REP --> DB2, now DB1 waits until REP says all
>DBs in cluster received ROW1. 
>
>INSERT ROW2, suppose it goes from LB --> DB2 --> REP -->DB1. In this
>situation: DB1 still waits response from REP for ROW1, DB2 waits for ROW2.
>It seems to me like a deadlock.
>
>Is this scenario possible with pgCluster? 
>
>I tested pgCluster 1.9 (normal flow: first start all DBs, start REP, start
>LB), with 6 concurrent Java threads inserting rows in the same table, I get
>an apparently infinitely wait.
>
>Am I doing something wrong?
>
> 
>
>                                   Have a nice day,
>
>                                               Lia.
>
> 
>
>
>_______________________________________________
>Pgcluster-general mailing list
>Pgcluster-general at pgfoundry.org
>http://pgfoundry.org/mailman/listinfo/pgcluster-general
>