Re: Shared_buffers hint - Mailing list pgsql-admin

From Marcelo Martins
Subject Re: Shared_buffers hint
Date
Msg-id 1538D014-0A5A-4DC1-928A-446E8A783267@zeroaccess.org
Whole thread Raw
In response to Shared_buffers hint  ("Rafael Domiciano" <rafael.domiciano@gmail.com>)
Responses About pg_hba.conf
List pgsql-admin
Hi Rafael,

The result there means that the minimal should be 4.69Mb for shared_buffers
As a rule of thumb the shared buffers should be between 10% - 15% of available RAM that assuming such is a dedicated PG server.
I have worked on some servers where I set shared buffers lower than 10%,  it's really a matter of trying out what value works best for  you.


Marcelo
Linux/Solaris System Administrator

On Oct 6, 2008, at 6:52 AM, Rafael Domiciano wrote:

HI people,

I'm tuning a server that is a long time abandoned, and this server is a little slow.
Now, in my postgresql.conf I have:
shared_buffers = 100Mb
mas_fsm_relations = 15000
mas_fsm_pages = 1600000
max_connections = 300

And I changin' to:
shared_buffers = 1000Mb
   (The server has 2 Gb of memory)
mas_fsm_relations = 15000
   (The Vacuum noticed me 608 relations)
mas_fsm_pages = 1600000
   (The Vacuum noticed me 500800 pages)
max_connections = 300
   (I did a "ps axf | grep postgres | wc -l" and the bash brings to me the number of 120 and all the people is not online at now)

My qustion is about shared_buffers, in postgresql.conf I have: min 128kB or max_connections*16kB  # (change requires restart)
So I did:
300 * (16Kb / 1024) = 4,69?
What this result means?

Thnks all,

Rafael Domiciano

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