RE: [GENERAL] Please help with performance tuning on Postgres

Yes, you assume correctly. I have read the FAQ. The only problem is the
FAQ's answer is nice, short, and sweet, but does not have any good real
world examples or real details.. The only details it mentions is that
setting shared memory buffers too high can cause it to crash, and so forth.
What is too high? Is there a formula or rule of thumb that you can use?
Possibly based on amount of available memory or memory your willing to
'dedicate' to the process, the number of back end processes, etc?

What I am looking for is some help from people who have tuned their
databases and can offer some insight. For example, the same performance
gains may be possible with multiple parameter settings, however, one group
of settings may be less 'expensive' than another. Or, you may be able to get
almost the same performance gain from a less expensive change than you do
with changes that consume a lot more resources.

That kind of information is obtained from people who have gone through this
process already, and have either learned the hard way, or picked up tricks
from others. If these people can share their experience, then others such as
myself can avoid reinventing the wheel. That is what I am searching for.

Thanks for the directions to the FAQ. It is also in the 'doc' directory of
the pgsql distribution.

Greg

Gregory S. Youngblood
ext 2164
 
 

-----Original Message-----
From: Bruce Momjian [mailto:maillist(at)candle(dot)pha(dot)pa(dot)us]
Sent: Saturday, October 03, 1998 5:55 PM
To: YoungblG(at)houstoncellular(dot)com
Subject: Re: [GENERAL] Please help with performance tuning on Postgres

I assume you have read the FAQ item on performance. It is on the web
site.

> I have a database running fine, however, it is purely stock configuration.
I
> would like to fine tune it for better performance and to control memory
> usage.
>
> I have seen people refer to restricting the number of back end processes,
> and fine tuning maximum memory consumption as well as other items.
>
> I've read the man pages, and a few options look promising, such as -B on
> postmaster and -S on postgres. However, I can't find anything that
explains
> what exactly those options will do, and the ramifications of changing them
> away from defaults.
>
> I also can't find any mention of restricting the number of simultaneous
> connections. Or, restricting the number of back end processes that can be
> run.
>
> The database will have a lot of information, but has no need to run more
> than maybe 4 to 12 backend processes. I would estimate that it wouldn't
need
> more than 6 unless special circumstances arose.
>
> This database is going to sit behind a web based front end. There won't be
a
> lot of simultaneous queries on the system, in normal operations. The web
> will be used as a query tool. Data modifications and updates will probably
> be via Access and ODBC, but that may change to some web based
modifications
> and updates at a later time.
>
> Does anyone have any pointers to fine tuning memory and performance
details
> of Postgres? I would really like to find something that documents not only
> what things do, but what ramifications of certain operations are. I want
to
> understand the performance tuning, not just copy someone's prewritten
> instructions.
>
> Thanks.
> Greg
>
> Gregory S. Youngblood
> ext 2164
>
>
>
>
>
>
>

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