[TYPO3-v4] Core performance for 4.6 and beyond

[Jigal van Hemert]

Hi,

I'm a bit worried by the MySQL bashing in this thread. If queries are 
slow it usually indicates one or more of the following:
- incorrect table structure
- incorrect engine
- incorrect indexes
- incorrect queries
- incorrect configuration

The Yahoo! Finance sites have been running very fast on MySQL database 
for a long time (I don't know if they still use MySQL; those decisions 
are often made for reasons other than technical arguments).

First of all, tables of 10,000 records are small for a database. If they 
are still slow then there is a serious problem with the way they are set 
up or used.
InnoDB is often used in high-concurrency situations (many simultaneous 
read and write operations), but with small tables it might still perform 
worse than MyISAM.

Seemingly simple operations can by quite expensive and often the 
solution is equally simple. A list of the 10 latest records in a table 
with half a million records was rather slow (back in the days of MySQL 
4.1). A simple explain showed that first all records were sorted and 
then the top 10 records were retrieved. Adding a condition to select 
only the records of the last two weeks (each day at least two records 
were added) increased the speed with a factor 100 or so.

Maybe part of the process of speeding up TYPO3 should be that we do some 
measurements first regarding which queries are performed most often and 
which queries are the slowest (especially in larger installations).
The results may lead to changes in the database structures (which might 
break some extensions), extra or modified indexes or restructured queries.

-- 
Kind regards / met vriendelijke groet,

Jigal van Hemert
skype:jigal.van.hemert
msn: jigal at xs4all.nl
http://twitter.com/jigalvh