Skip site navigation (1) Skip section navigation (2)

Re: PostgreSQL clustering VS MySQL clustering

From: Frank Wiles <frank(at)wiles(dot)org>
To: alex(at)neteconomist(dot)com
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: PostgreSQL clustering VS MySQL clustering
Date: 2005-01-28 16:17:24
Message-ID: 20050128101724.6777241d.frank@wiles.org (view raw or flat)
Thread:
Lists: pgsql-performance
On Fri, 28 Jan 2005 10:59:58 -0500
Alex Turner <armtuk(at)gmail(dot)com> wrote:

> At this point I will interject a couple of benchmark numbers based on
> a new system we just configured as food for thought.
> 
> System A (old system):
> Compaq Proliant Dual Pentium III 933 with Smart Array 5300, one RAID
> 1, one 3 Disk RAID 5 on 10k RPM drives, 2GB PC133 RAM.  Original
> Price: $6500
> 
> System B (new system):
> Self Built Dual Opteron 242 with 2x3ware 9500S-8MI SATA, one RAID 1
> (OS), one 4 drive RAID 10 (pg_xlog), one 6 drive RAID 10 (data) on 10k
> RPM Raptors, 4GB PC3200 RAM.  Current price $7200
> 
> System A for our large insert job: 125 minutes
> System B for our large insert job: 10 minutes.
> 
> There is no logical way there should be a 12x performance difference
> between these two systems,  maybe 2x or even 4x, but not 12x
> 
> Bad controler cards/configuration will seriously ruin your day.  3ware
> escalade cards are very well supported on linux, and work excellently.
>  Compaq smart array cards are not.  Bonnie++ benchmarks show a 9MB/sec
> write, 29MB/sec read on the RAID 5, but a 172MB/sec write on the
> 6xRAID 10, and 66MB/sec write on the RAID 1 on the 3ware.
> 
> With the right configuration you can get very serious throughput.  The
> new system is processing over 2500 insert transactions per second.  We
> don't need more RAM with this config.  The disks are fast enough. 
> 2500 transaction/second is pretty damn fast.

  I agree that badly supported or configured cards can ruin your
  performance. 

  However, don't you think moving pg_xlog onto a separate RAID and
  increasing your number of spindles from 3 to 6 on the data RAID would
  also have a significant impact on performance, no matter what card was
  used? 

  I'm not sure you can give all the credit to the card on this one. 

 ---------------------------------
   Frank Wiles <frank(at)wiles(dot)org>
   http://www.wiles.org
 ---------------------------------


In response to

pgsql-performance by date

Next:From: Merlin MoncureDate: 2005-01-28 16:19:44
Subject: Re: PostgreSQL clustering VS MySQL clustering
Previous:From: Tom LaneDate: 2005-01-28 16:13:46
Subject: Re: Bitmap indexes

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group