Re: Postgres scalability and performance on windows - Mailing list pgsql-performance

From Heikki Linnakangas
Subject Re: Postgres scalability and performance on windows
Date
Msg-id 456625C5.1050601@enterprisedb.com
Whole thread Raw
In response to Postgres scalability and performance on windows  ("Gopal" <gopal@getmapping.com>)
List pgsql-performance
Gopal wrote:

> Functions : Simple coordinate reprojection and intersection query +
> inner join of table1 and table2.
>
> I think I have all the right indexes defined and indeed the performance
> for  queries under low loads is fast.

Can you do a EXPLAIN ANALYZE on your queries, and send the results back
to the list just to be sure?

> SQL server caches all the data in memory which is making it faster(uses
> about 1.2GB memory- which is fine).
>
> But postgres has everything spread across 10-15 processes, with each
> process using about 10-30MB, not nearly enough to cache all the data and
> ends up doing a lot of disk reads.

I don't know Windows memory management very well, but let me just say
that it's not that simple.

> I've read that postgres depends on OS to cache the files, I wonder if
> this is not happenning on windows.

Using the Task Manager, or whatever it's called these days, you can see
how much memory is used for caching.

--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com

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