[Typo3-dev] RealURL : high server load and optimization

[Jan-Erik Revsbech]

> I am currently writing a little BE module that hooks into one of the
> *SELECT* functions in class.t3lib_db.php
> I am going to log all select to the DB and see  what  'where' clauses
> are used mostly and doign index optimalisations
> based on these statistics...
>
> any thought about that?
>

You could also just turn on the slow queries log in MySQL, it has an option 
to log all queries which are not using an index.

I have done what you suggest above (making DBAL log queires which run 
slowly) and generelly find that TYPO3 is well optimized in most cases (there 
are some exceptions, but mostly with extension).  One (as I see it) big 
problem is the comma seperated list, which are not easyly indexed. Having 
20.000+ be_users nested into groups make a *lot* of slow queries due to the 
comma list used to associate groups with their parent group. There is really 
something to gain here, but only if you have many be_users. As I understand 
the patch for 4.0 which enables nested fe_groups also uses comma lists, 
which might affect large sites with nested groups.

>
> cheers,
> Ries

/Jan-Erik