[Pgcluster-general] PgCluster and concurrency

[Lia Domide]

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.

 

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