pg.ddx.io  pgsql-performance@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Steve Poe <spoe@sfnet.cc>
To: Thomas F.O'Connell <tfo@sitening.com>
Cc: PgSQL - Performance <pgsql-performance@postgresql.org>
Subject: Re: pgbench Comparison of 7.4.7 to 8.0.2
Date: Fri, 15 Apr 2005 14:24:55 -0700
Message-ID: <42603127.5070108@sfnet.cc> (raw)
In-Reply-To: <2784476415a96bb0912ebca41edb3d84@sitening.com>
References: <2784476415a96bb0912ebca41edb3d84@sitening.com>

Tom,

People's opinions on pgbench may vary, so take what I say with a grain 
of salt. Here are my thoughts:

1) Test with no less than 200 transactions per client. I've heard with 
less than this, your results will vary too much with the direction of 
the wind blowing. A high enough value will help rule out some "noise" 
factor. If I am wrong, please let me know.


2) How is the database going to  be used?  What percentage will be 
read/write if you had to guess? Pgbench is like a TPC-B with will help 
guage the potential throughput of your tps. However, it may not stress 
the server enough to help you make key performance changes. However, 
benchmarks are like statistics...full of lies <g>.

3) Run not just a couple pgbench runs, but *many* (I do between 20-40 
runs) so you can rule out noise and guage improvement on median results.

4) Find something that you test OLTP-type transactions. I used OSDB 
since it is simple to implement and use. Although OSDL's OLTP testing 
will closer to reality.

Steve Poe



view thread (10+ messages)  latest in thread

Message-ID: <42603127.5070108@sfnet.cc>
Permalink:  ../42603127.5070108@sfnet.cc/
Also on:    postgresql.org/message-id/42603127.5070108@sfnet.cc

 · 

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-performance@postgresql.org
  Cc: spoe@sfnet.cc, tfo@sitening.com
  Subject: Re: pgbench Comparison of 7.4.7 to 8.0.2
  In-Reply-To: <42603127.5070108@sfnet.cc>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox