Re: Shared_buffers hint

[Marcelo Martins <pglists@xxxxxxxxxxxxxx>]

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

http://www.zeroaccess.org

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