Re: OSDL DBT-2 w/ PostgreSQL 7.3.4 and 7.4beta5

Christopher Kings-Lynne <chriskl@familyhealth.com.au>

From: Christopher Kings-Lynne <chriskl@familyhealth.com.au>
To: Mark Wong <markw@osdl.org>
Cc: Rod Taylor <rbt@rbt.ca>, PostgreSQL Development <pgsql-hackers@postgresql.org>, OSDL - DB General <osdldbt-general@lists.sourceforge.net>
Date: 2003-11-02T03:03:34Z
Lists: pgsql-hackers
Numerics are a LOT slower than reals.  Integers are faster than anything 
I guess.

Chris

Mark Wong wrote:

> I don't remember making a conscious decision between the number and integer
> database type.  Is that a significant oversight on my part?
> 
> 
> On Fri, Oct 31, 2003 at 08:04:34PM -0500, Rod Taylor wrote:
> 
>>Excellent.
>>
>>I just noticed that most of the numbers in the system are given the
>>numeric data type. Is there any particular reason you don't use integer
>>(test enforced?)?
>>
>>On Fri, 2003-10-31 at 19:18, markw@osdl.org wrote:
>>
>>>I thought someone might be interested in a data point I have comparing
>>>7.3.4 and 7.4beta5 with results from our DBT-2 workload. Keep in mind I
>>>haven't done much tuning with either version.  The following links have
>>>references iostat, vmstat, sar, readprofile (linux kernel profile), and
>>>oprofile (postgresql profile) statistics.
>>>
>>>Results from 7.3.4:
>>>	http://developer.osdl.org/markw/dbt2-pgsql/184/
>>>	- metric 1354.58
>>>
>>>Results from 7.4beta5
>>>	http://developer.osdl.org/markw/dbt2-pgsql/188/
>>>	- metric 1446.01
>>>
>>>7.4beta5 offers more throughput.  One significant difference I see is in
>>>the oprofile for the database.  For the additional 7% increase in the
>>>metric, there are about 32% less ticks in SearchCatCache.
>>>
>>>These are the only database parameters I've explicitly set for each one,
>>>any other differences will be differences in default values:
>>>	- shared_buffers = 40000
>>>	- tcpip_socket = true
>>>	- checkpoint_segments = 200
>>>	- checkpoint_timeout = 1800
>>>	- stats_start_collector = true
>>>	- stats_command_string = true
>>>	- stats_block_level = true
>>>	- stats_row_level = true
>>>	- stats_reset_on_server_start = true
>>>
>>>If anyone has any tuning recommendations for either 7.3 or 7.4, I'll be
>>>happy to try them.  Or if anyone wants to be able to poke around on the
>>>system, we can arrange that too.  Feel free to ask any questions.
> 
> 
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