[pgpool-general: 602] Re: About configuration parameters

[Lazaro Ruben Garcia Martinez]

Tatsuo, sorry for my questions. It is not my intention to criticize the documentation because I think the documentation of pgpool-II is very good. I just write you because I need understand some things that I do not know. Maybe my questions are not writen in a good way. 

When max_pool has a value such as 4. It means that the same child process can be opened 4 connections regardless of the connections that can be reused? 

Thank you very much for your time. 

Regards. 

----- Mensaje original -----


> Hello everyone in the list. In other mails I asked about this topic, but I have some doubt with this configuration parameters. As I know, connection pooling software like pgpool-II, has a number of connections opened and reuses them whenever a new connection with the same properties comes in. 
> 
> About these configuration parameters: 
> 
> max_connections: Is the maximum concurrent connections between clients and postgresql server. (postgresql property) 
> 
> num_init_children: Like max_connections, it is the maximum concurrent connections between clients and pgpool-II. (pgpool property) 
> 
> max_pool: The maximum number of cached connections in pgpool-II children processes. pgpool-II reuses the cached connection if an incoming connection is connecting to the same database with the same username. If not, pgpool-II creates a new connection to the backend. If the number of cached connections exceeds max_pool, the oldest connection will be discarded, and uses that slot for the new connection. (According pgpool-II documentation) 
> 
> 
> 1. Why max_connexion must satisfy this formula max_connexion >= (Nun_init_children * max_pool) and not this max_connexion >= nun_init_children? 
> 
> 2. A child process only opens one connection in the database server and it can be use concurrently (max_pool), or for each child process, it open a total of max_pool connections in the database server? 
> 
> 3. When is possible that the number of cached connections exceeds max_pool? 

Have you read this section in the pgpool doc? If yes and still have 
questions please clarify. I would love to hear from you to enhance our 
document. 

<dt><a name="MAX_POOL"></a>max_pool</dt> 
<dd> 
<p>The maximum number of cached connections in pgpool-II children processes. 
pgpool-II reuses the cached connection if an incoming connection is 
connecting to the same database with the same username. 
If not, pgpool-II creates a new connection to the backend. 
If the number of cached connections exceeds max_pool, 
the oldest connection will be discarded, and uses that slot for the new connection. 

> The answers about these questions are welcome. 
> Thank you very much for your time and sorry for such insistence. 
> Regards 
> 
> 
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10mo. ANIVERSARIO DE LA CREACION DE LA UNIVERSIDAD DE LAS CIENCIAS INFORMATICAS... 
CONECTADOS AL FUTURO, CONECTADOS A LA REVOLUCION 

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10mo. ANIVERSARIO DE LA CREACION DE LA UNIVERSIDAD DE LAS CIENCIAS INFORMATICAS...
CONECTADOS AL FUTURO, CONECTADOS A LA REVOLUCION

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http://www.facebook.com/universidad.uci
http://www.flickr.com/photos/universidad_uci
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