Skip site navigation (1) Skip section navigation (2)

max_connections and shared_buffers

From: "Anoo Sivadasan Pillai" <aspillai(at)in(dot)rm(dot)com>
To: <pgsql-admin(at)postgresql(dot)org>
Subject: max_connections and shared_buffers
Date: 2007-09-03 03:51:16
Message-ID: 772CDA49C515244FA14E34443F62E56402F17349@EX-INDIA1.internal.rmplc.net (view raw or flat)
Thread:
Lists: pgsql-admin
Hi, 

1)      I saw a comment from experts-exchage  regarding shared_buffers,
where max_connections were 600

"2000 shared buffers were for 40 connections
For 600 connections it looks more like 30000 shared buffers - to prevent
weekly slowdown.
i.e 8KB*30000 = 240MB

16M work_mem * 600 = 9600MB maximum when everyone is connected. " 

 

Can anybody explain the logic behind the calculation?

Why 30000 shared buffers is suggested for 600 connections.  

Postgresql help says "This setting must be at least 128 kilobytes and at
least 16 kilobytes times max_connections
<mk:@MSITStore:C:\Program%20Files\PostgreSQL\8.2\pgAdmin%20III\docs\en_U
S\pgadmin3.chm::/pg/runtime-config-connection.html#guc-max-connections>
." 

 

2)  I want to set  max_connections=1024

Can anybody help to suggest a proper value for shared buffers for the
settings ( if no other settings are counted ) 

 

Anoo

 

 
Visit our Website at http://www.rmesi.co.in

This message is confidential. You should not copy it or disclose its contents to anyone. You may use and apply the information for the intended purpose only. Internet communications are not secure; therefore, RMESI does not accept legal responsibility for the contents of this message. Any views or opinions presented are those of the author only and not of RMESI. If this email has come to you in error, please delete it, along with any attachments. Please note that RMESI may intercept incoming and outgoing email communications. 

Freedom of Information Act 2000
This email and any attachments may contain confidential information belonging to RMESI.  Where the email and any attachments do contain information of a confidential nature, including without limitation information relating to trade secrets, special terms or prices these shall be deemed for the purpose of the Freedom of Information Act 2000 as information provided in confidence by RMESI and the disclosure of which would be prejudicial to RMESI's commercial interests.

This email has been scanned for viruses by Trend ScanMail.


Responses

pgsql-admin by date

Next:From: Scott MarloweDate: 2007-09-03 04:18:40
Subject: Re: max_connections and shared_buffers
Previous:From: Simon RiggsDate: 2007-09-02 21:06:40
Subject: Re: pitr replica dies on startup

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group