[pgpool-general: 255] Slow Pgpool performance on load balancing

[aT]

Hi ,

I am seeing slow performance when do pgbench test for Selects  via pgpoolII
compared to performing same test over the backend .

The setup is following .

1 Master  - 2 Salve  Streaming replication setup .

PgpoolII resides on Master node .

All node have exact software versions and hardware .

Postgres version  (9.1.3)
pgpoolII version  3.2alpha1  ( loadbalancing enabled )


These are pgbench test , there is a huge difference with and without
pgpoolII . Any idea whats the cause ? Shouldnt the select test with pgpool
be able to handle more transactions than single backend ?

*Test 1 :*
*$ pgbench -p9999 -T 30 -S -n -c 12 bench_replication*
*transaction type: SELECT only*
*scaling factor: 1*
*query mode: simple*
*number of clients: 12*
*duration: 30 s*
*number of transactions actually processed: 562902*
*tps = 18762.431859 (including connections establishing)*
*tps = 18791.333944 (excluding connections establishing)*
*
*
*$ pgbench -p5432 -h 10.52.6.142 -T 30 -S -n -c 12 bench_replication*
*transaction type: SELECT only*
*scaling factor: 1*
*query mode: simple*
*number of clients: 12*
*duration: 30 s*
*number of transactions actually processed: 1133075*
*tps = 37767.193960 (including connections establishing)*
*tps = 37800.532288 (excluding connections establishing)*

*Test 2: -C*
*$ pgbench -p5432 -h 10.52.6.142 -t 20 -S -n -C -c 10 bench_replication*
*transaction type: SELECT only*
*scaling factor: 1*
*query mode: simple*
*number of clients: 10*
*number of transactions per client: 20*
*number of transactions actually processed: 200/200*
*tps = 386.054924 (including connections establishing)*
*tps = 28364.770954 (excluding connections establishing)*

*$ pgbench -p9999  -t 20 -S -n -C -c 10 bench_replication*
*transaction type: SELECT only*
*scaling factor: 1*
*query mode: simple*
*number of clients: 10*
*number of transactions per client: 20*
*number of transactions actually processed: 200/200*
*tps = 303.073927 (including connections establishing)*
*tps = 3775.508278 (excluding connections establishing)*

-- 
Syed Atif Ali
Desk: 971 4 4493131
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