The benefits of tuning

[Haircut]

I thought I'd create this thread for the benefit of anyone that thinks tuning isn't necessary in todays world with so much CPU power on tap.

I work for a large company who has just had a new system developed, like any new system there have been a few teething problems and one of the users' main gripes was the speed (or lack of it) of the new application.

So, we looked on the database and the UNIX box on which the database was running and saw the problem.

We don't exactly have an underpowered box for this thing (16 x 1.2 GHz UltraSparc IVs with 64Gb of RAM) but we were seeing that it was completely maxed out during working hours.
A quick look on the database showed that during the 8 hours of a working day in April there were 5.6 billion logical reads

Obviously there was a concerted effort to tune as much code as possible and the last of the current phase went in yesterday.

Now we are showing only 1.6 billion reads in the same time period, much more CPU free and some much happier users.

Next time someone says that you don't have to bother making things efficient nowadays I'd take the advice with a pinch of salt!

 

[Dj_Jestar]

Equally as important, don't try and pre-optimise your code! Get it working, then tune it.

We (my employers) recently saw a project fail it's deadline miserably because the developers were all too busy optimising the little bits without looking at the bigger picture and getting the app working as a whole, before optimising it.

 

[Beansprout]

Very good point, I was thinking of making a thread like this too.

Yesterday a large photo gallery we host received visits by, well...a university mailing list, which equated to nearly 400,000 pageviews in a few hours....but after fiddling with the gallery software (Gallery 2) and enabling some performance tweaks, the load more than tenth'd as the system used its cache rather than dynamically loading most things.

Efficiency and tuning is incredibly important because eventhough CPU power has risen, people forget that the number of users and complexity of apps has also risen