[pgpool-general: 6739] Re: Request for suggestion on Resource requirment(CPU, RAM) for 4000 pgpool concurrent connections.

[Tatsuo Ishii]

First of all, please do not cross post your message. Your question is
not related to Pgpool-II development/hacking, so please post to
pgpool-general only. (I removed reply to pgpool-hackers).

> Hi Team,
> 
> Good day,
> 
> We have got requirement to setup pgpool for handling 4000 concurrent users.

Wao. That's too much, I am afraid. I suggest to think again about the
requirement if it's actually needed...

Also I suggest to ask in pgsql-general ML if 4000 concurrent
connections to PostgreSQL is doable or not because 4000 cocurrent
users to pgpool means 4000 concurrent users of PostgreSQL at the same
time.

> Could you please help me to calculate the required hardware resources (CPU,
> RAM) to handle 4000 concurrent users.
>
> Please share if you have any thump rules to calculate the pgpool resource
> estimations.

There's no calculation rule explained in existing documents but
upcoming Pgpool-II 4.1 will have such a section. You can preview here:

http://tatsuo-ishii.github.io/pgpool-II/current/resource-requiremente.html#MEMORY-REQUIREMENT

> We are planning to use 4 backend DB nodes for load balancing purpose as
> well.
> 
> Please let me know max_connections to each backend DB to cater 4000
> concurrent users at pgpool level.

It's explained in the doc.
https://www.pgpool.net/docs/37/en/html/runtime-config-connection.html#RUNTIME-CONFIG-CONNECTION-SETTINGS

> Please suggest is connections pooling helps in this?, if yes please suggest
> max_pool connections.

I suggest to keep max_pool to 1. Since there's already too many max_connections needed.

Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp