Message-ID: <43FF92EB.7060704@modgraph-usa.com>
Date: Fri, 24 Feb 2006 15:12:43 -0800
From: "Craig A. James" <cjames@modgraph-usa.com>
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To: "Joshua D. Drake" <jd@commandprompt.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Reliability recommendations
References: <200602241429.k1OETwD07991@candle.pha.pa.us>
	<43FF2095.6050505@modgraph-usa.com>
	<43FF403D.8090305@commandprompt.com>
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Joshua D. Drake wrote:
>> I find this strains credibility, that this major manufacturer of PC's 
>> would do something deceptive that hurts performance, when it would be 
>> easily detected and widely reported.  Can anyone cite a specific 
>> instances where this has happened?  Such as, "I bought Dell model XYZ, 
>> which was advertised to have these parts and these specs, but in fact 
>> had these other parts and here are the actual specs."
> 
> I can :)
> 
> Feb 20 07:33:52 master kernel: [4294682.803000]   Vendor: MegaRAID  
> Model: LD 0 RAID1   51G  Rev: 196T
> --- snip ---
> This machine... if you run it in raid 5 will only get 7-9 megabytes a 
> second READ! performance. That is with 6 SCSI drives.
> If you run it in RAID 10 you get a more reasonable 50-55 megabytes per 
> second.

But you don't say how this machine was advertised.  Are there components in that list that were not as advertised?  Was the machine advertised as capable of RAID 5?  Were performance figures published for RAID 5?

If Dell advertised that the machine could do what you asked, then you're right -- they screwed you.  But if it was designed for and advertised to a different market, then I've made my point: People are blaming Dell for something that's not their fault.

Craig