Re: Load overshooting ONE server

From: The Natural Philosopher <tnp_at_invalid.invalid>
Date: Wed, 7 Sep 2016 16:57:42 +0100
Message-ID: <nqpddn$o9o$1_at_news.albasani.net>


On 07/09/16 16:25, Michael Vilain wrote:
> "Unless a system is poorly tuned at the start, usually you'll only get
> at best 10% increase by spending time tuning a system. However, if an
> application is poorly designed, you can get massive increases in
> performance and throughput by tuning that application."
>
> Which still seems to apply, even today. Tune the application first,
> then throw hardware at it. If it doesn't scale well, go back and
> rethink the design so that it will scale.

Absolutely true. The truism that mysql isn't very good at complex queries has been confirmed by several people I know who use it.

Look at what the application is doing and test the primary queries or inserts.

If they are dog slow, look at indices. Or break the complexity into simple parts.

[Quoted] [Quoted] IN particular I found that a nested query was far better performed by the application than by Mysql, on a multi-million record table

But of course all bets are off if the system is running into swap....

-- 
All political activity makes complete sense once the proposition that 
all government is basically a self-legalising protection racket, is 
fully understood.
Received on Wed Sep 07 2016 - 17:57:42 CEST

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