> I'm running Postgres 8.1.11. Here are the results of a pgbench test > pgbench -c 20 -t 1000 testdb > starting vacuum...end. > transaction type: TPC-B (sort of) > scaling factor: 1 > number of clients: 20 > number of transactions per client: 1000 > number of transactions actually processed: 20000/20000 > tps = 731.350579 (including connections establishing) > tps = 732.860160 (excluding connections establishing) > > I set up another environment with 3 servers 1 pgpool server and 2 masters > for master-master replication. Everything on the pgpool functions great but > the performance is terrible. Here are the results of the same pgbench test > run on the pgpool cluster. > pgbench -p 9999 -c 20 -t 1000 testdb > starting vacuum...end. > transaction type: TPC-B (sort of) > scaling factor: 1 > number of clients: 20 > number of transactions per client: 1000 > number of transactions actually processed: 20000/20000 > tps = 443.242941 (including connections establishing) > tps = 443.912381 (excluding connections establishing) > tps = 401.669441 (excluding connections establishing) > > > All four servers have exactly the same hardware configuration. > > Is this performance loss normal?
Yes. I think existing shared-nothing-synchronous-replication softwares including PGCluster will show more or less same performance. I should note that while other such replication softwares show the performance degration almost propotional to the numbers of PostgreSQL servers, pgpool's performance is not worse than 1/2 of PostgreSQL. Also please note that READ query performance will increase according to the numbers of PostgreSQL servers. So you have a chance to get performance boost if most of your quries are READ. Of course this may vary to the characteristics of load though. -- Tatsuo Ishii SRA OSS, Inc. Japan _______________________________________________ Pgpool-general mailing list [email protected] http://pgfoundry.org/mailman/listinfo/pgpool-general
