Re: How to measure the speed

In article <1994Oct3.234552.20637_at_rossinc.com>

           joelga_at_rossinc.com "Joel Garry" writes:

> In article <364s83$oei_at_netnews.upenn.edu> ling_at_underground.irhe.upenn.edu (Mark
> Ling) writes:
> >Hi , there:
> > I have a very simple question: My client asked me that How long I need to
> >search one recorder from a 500*half million data table in Oracle data base,
> >the Oracle was installed in 486DX66 server which is hooked up by ether net.
> >My client's bottom line is 3 second, is it possible? how can I know whether
> >it's possible or not? If it is impossible, updating the computer server, say
> >using Pentinm 100 , can reach that goal(3 second for searching one
> >recorder)?
> >
> > Thank you for your help in advance.
> >
> Well, this is not a simple question. First of all, I assume you mean
> record. In relational databases, we call those rows. So you are
> asking, "How long will it take to find any random record out of a
> 500,000 row table?"
>
> The answer is, not only do I not know, but there isn't even any theory
> to figure it out. The reason for that is there is no time in relational
> theory. What has been proven is, that does not mean other theoretical
> models will provide better performance. The question you have asked
> presupposes a hierarchical model - there you can use various queueing
> theories to figure out how long it will take. Basically, you would
> figure out how long it takes to get a particular record, including time
> for head movement and disk rotational latency and all that bs.
>
> [stuff deleted]

Get yourself a good independent benchmark consultant and try it out. Don't know the scene over the pond, but in UK, E2 Systems are good. Based on taking the real application, or something enough like it, and using some special software to make the target machine think that zillions of users are hitting it.

-- 
Tom Cooke               tom_at_tomcooke.demon.co.uk             +44 (0)1782 748027
North Staffordshire Hospital Computer Centre, Stoke-on-Trent, Staffordshire, UK