Hello there! I am currently evaluating the best solution for a high-availability, load balanced cluster. Currently I am testing this environment : postgres 8.3.1, pgpool-II 2.1, Slony-I 1.2.14. I've setup a master server to replicate all tables with Slony-I to a slave, and a frontend with pgpool that load-balances the queries (load_balance=true, replication_mode=false, parallel_query=false, enable_query_cache=false).
There is a problem : a stored procedure that returns a sequence value (a global unique ID, used as primary key in INSERTs) returns the same values in successive calls, under certain conditions. This is clearly due to the replication lag led by Slony-I. I would call it a race condition. Now the question : is there a way to force pgpool to redirect all queries that involves a specific sequence or a stored procedure to a specific backend? I tried to setup query partitioning, but only tables are supported so far. I know that all queries belonging to a single transaction should be redirected to the same backend, but I would like to find out a solution working on the backend, avoiding to check a huge amount of code that works. ;) I also know that using the pgpool replication mode will solve the issue, but it can lead to downtime when adding new backends, since a synch operation is required. Slony-I implement replication in a more suitable way from this point of view. Thanks in advance! Regards, Andrea Moretto Andrea Moretto [EMAIL PROTECTED] ------------------------------------------------------- CONFIDENTIALITY NOTICE This message and its attachments are addressed solely to the persons above and may contain confidential information. If you have received the message in error, be informed that any use of the content hereof is prohibited. Please return it immediately to the sender and delete the message. ------------------------------------------------------- _______________________________________________ Pgpool-general mailing list [email protected] http://pgfoundry.org/mailman/listinfo/pgpool-general
