[pgpool-general: 8014] Re: connection is not available

[Tatsuo Ishii]

> According the documentation for support 3000 child processes Pgpool
> requires 15Gb RAM.
> 
> Could you tell are there any experiences with large number of
> num_init_children?

No. Sorry.

> And second question if don't mind.
> 
> The application works by 5 services and serves 100 client
> connections. I mean that 100 clients are connected to 5 services (20
> on each).
> 
> 5 services connect to database via Pgpool. Connection user in each
> service is the same. Each service works with one database only.
> 
> Which variant of configuration parameters would be better -
> 
> num_init_children=100 and  max_pool=1 (2)
> 
> OR
> 
> num_init_children=5 and  max_pool=20

I hardly understand your system configuration. So I cannot tell which
is (or any other) better. Can you clarify from the perspective of
PostgreSQL server? I mean:

1) I assume you have 1 PostgreSQL primary and some number of standby
  servers in streaming replication configuration. They have exactly
  same database cluster. Am I correct?

2) If #1 is correct, how many databases and database users do you
have? My wild guess is each "service" is related to each database. So
you have 5 databases? Number of database users is same as "connection
users"? If so, probably number of database users is 100?

> Regards,
> Nikolay
> 
> 31.01.2022 14:11, Tatsuo Ishii пишет:
>>> [NM]: We will need establish 3000+ connections in our perspective.
>>>
>>> Can we increase num_init_children until 3000?
>> I don't know. It will depends on the hardware. 3000 is not small
>> number. You will need carefull testing.
>>
>>> How much computing resources of the CPU and RAM may be needed in this
>>> case?
>> Apparently more CPU is bette. For RAM and other resources please see
>> the manual.
>>
>> https://www.pgpool.net/docs/latest/en/html/resource-requirement.html
>>
>> Best reagards,
>> --
>> Tatsuo Ishii
>> SRA OSS, Inc. Japan
>> English: http://www.sraoss.co.jp/index_en.php
>> Japanese:http://www.sraoss.co.jp