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Date: Tue, 31 Jan 2012 12:21:38 +0100
Subject: Re: How to improve insert speed with index on text column
From: "Tomas Vondra" <tv@fuzzy.cz>
To: "Saurabh" <saurabh.b85@gmail.com>
Cc: pgsql-performance@postgresql.org
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On 31 Leden 2012, 10:29, Saurabh wrote:
> I changed the configuration in postgresql.conf. Following are the
> changed parameters:
>
> shared_buffers =3D 1GB
> maintenance_work_mem =3D 50MB
> checkpoint_segments =3D 64
> wal_buffers =3D 5MB
> autovacuum =3D off
>
> Insert the records in the database and got a very good performance it
> is increased by 6 times.
>
> Can you please tell me the purpose of shared_buffer and
> maintenance_work_mem parameter?

Shared buffers is the cache maintained by PostgreSQL. All all the data
that you read/write need to go through shared buffers.

Maintenance_work_mem specifies how much memory can "maintenance tasks"
(e.g. autovacuum, reindex, etc.) use. This is similar to work_mem for
common queries (sorting, grouping, ...).

Tomas