Re: Question about maintenance_work_mem and shared_buffer - Mailing list pgsql-admin

From Albe Laurenz
Subject Re: Question about maintenance_work_mem and shared_buffer
Date
Msg-id A737B7A37273E048B164557ADEF4A58B05820995@ntex2010a.host.magwien.gv.at
Whole thread Raw
In response to Question about maintenance_work_mem and shared_buffer  (Rodrigo Barboza <rodrigombufrj@gmail.com>)
Responses Re: Question about maintenance_work_mem and shared_buffer  (Rodrigo Barboza <rodrigombufrj@gmail.com>)
List pgsql-admin
Rodrigo Barboza wrote:
> I have a doubt.
> I have a 32-bit postrgesql running with 2.5gb of shared_buffer.
> And I have maintenance_work_mem = 1gb and autovacuum_max_workers = 3.
> How maintenance_work_mem is related to shared_buffer?
> If the 3 workers uses 1gb, will the database crash?
> Or their memory usage are separated from each other?

Your doubt is quite in place, as a process on a 32-bit architecture
cannot address more than 4GB of memory.

See http://rhaas.blogspot.jp/2011/05/sharedbuffers-on-32-bit-systems.html

shared_buffers plus the private memory of a backend shouldn't
exceed 3GB.

So I'd go for shared_buffers = 2GB and maintenance_work_mem much
smaller than 1GB.

Yours,
Laurenz Albe


pgsql-admin by date:

Previous
From: Amit Langote
Date:
Subject: Re: WAL files not following sequence
Next
From: lakkireddy
Date:
Subject: Re: Query is stuck