[ADMIN] Why pgpool TPS is lowest versus postgresql direct connections? - Mailing list pgsql-admin

From Lazaro Garcia
Subject [ADMIN] Why pgpool TPS is lowest versus postgresql direct connections?
Date
Msg-id 001d01d282bb$43909610$cab1c230$@gmail.com
Whole thread Raw
Responses [ADMIN] Re: [pgpool-general: 5318] Why pgpool TPS is lowest versus postgresql direct connections?  ("David Sisk -X (dsisk - TEKSYSTEMS INC at Cisco)" <dsisk@cisco.com>)
Re: [ADMIN] Why pgpool TPS is lowest versus postgresql direct connections?  (Jehan-Guillaume de Rorthais <ioguix@free.fr>)
List pgsql-admin

The correct results reported by sysbench was:

 

Concurrent Users

1

20

50

100

PostgreSQL

3582

11943

12852

10618

Pgpool

2240

7628

7013

6135

 

Is there any way to tuning this behavior?

 

Regards

 

 

De: Lazaro Garcia [mailto:lazaro3487@gmail.com]
Enviado el: miércoles, 8 de febrero de 2017 05:28 p. m.
Para: 'pgpool-general@pgpool.net'; 'pgsql-admin@postgresql.org'
Asunto: Why pgpool TPS is lowest versus postgresql direct connections?

 

After installed Pgpool with 2 postgresql nodes with streaming replication, I have noticed that access directly to postgresql is more efficient than through pgpool.

 

I supposed that load balance could increase the transactions per second executed because each node could receive more load, but the results shown below are not expected.

 

This is the setup:

 

Pgpool 3.6.1 whit connection pooling, streaming replication mode and load balancing mode.

 

2 PostgreSQL server 9.6.1 whit streaming replication.

 

For the tests I used sysbench and pgbench.

 

The results of sysbench:

 

Concurrent Users

1

20

50

100

PostgreSQL (TPS) Direct

1166

20936

25743

27344

Pgpool (TPS)

2240

7628

7013

6135

 

 

The results of pgbench

 

1

20

50

100

PostgreSQL (TPS) Direct

1403

6805

6194

5726

Pgpool (TPS)

511

5430

5528

4705

 

 

As you can see in both cases even with load balance, the total transactions per second are lower.

 

Is this the expected behavior. Is there any way to allow more TPS when pgpool is used?

 

There are other publications with similar results:

 

https://www.os3.nl/_media/2011-2012/courses/lia/rory_breuk_gerrie_veerman_-_report.pdf    (page 28)

http://www.mail-archive.com/pgpool-general@pgfoundry.org/msg03326.html

 

 

Regards

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