Re: The old raw devices chestnut.

"Niall Litchfield" <niall.litchfield_at_dial.pipex.com> wrote in message news:<407e22ba$0$16835$cc9e4d1f_at_news-text.dial.pipex.com>...
> "Andrew Hamm" <ahamm_at_mail.com> wrote in message
> news:c5ksg3$2p91m$1_at_ID-79573.news.uni-berlin.de...
> > Further (with Informix, once again) the engine can use KAIO, and with the
> > architecture of Informix, this can lead to further significant
> improvements.
> > It all adds up. Why do you think F1 now make their pedals out of carbon
> > fibre? And they *still* drill 'em out for extra lightness. An Informix
> > engine using raw with KAIO and a decent layout of spaces on the disk can
> > feel very spiffy indeed even compared to one that merely drops KAIO and
> raw.
>
> A dangerous analogy, the formula 1 one. An F1 Car is made to last a
> weekend - used to be a race - and to be rebuilt after that. This is not a
> desirable* thing in a database. Robustness and reliability are important as
> well as performance - probably more so.

Good point, Niall (especially the *). I think the better analogy might be fuel injection v. carburetors. Better performance AND gas mileage AND reliability eventually takes over the consumer market and the racing market (with some notable exceptions). So if raw is a nearly-free 20% performance gain, especially during month-end serial processing when people with purse strings are tapping their fingers on their desks, then it's likely to take over. And in a way it is, with the newfangled filesystems. But managing raw filesystems manually is like mulitple carburetors - great performance if you have the right tools, risky if you don't. Ever hear a six-carb V12? Hooo-mama.

>
>
> --
> Niall Litchfield
> Oracle DBA
> Audit Commission UK
> http://www.niall.litchfield.dial.pipex.com
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>
> *actually it is desirable in one situation - when running a TPC or similar
> benchmark. Again you engineer the product to last pretty much for the life
> of the performance test and sacrifice everything else for speed.

jg

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