[TYPO3-v4] Core performance for 4.6 and beyond

[Christian Kuhn]

Hey.

On 02/08/2011 09:24 AM, Jigal van Hemert wrote:
> 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

Sure! Don't get me wrong, Jigal: I love mysql for its performance and 
I'm not a bloody beginner in optimizing mysql. In fact the core queries 
are already optimized pretty well, in usual operation there are no wrong 
indexes or evil queries. We're running sites with up to 10k queries per 
second at peak time on mysql and it takes quite some time to get the 
configuration right after launch, to locate and fix slow queries of 
extensions and to optimize mysql to specific hardware (mostly memory) 
capabilities.

Most of our caching framework setups run with db backend (pages caches 
often with compression enabled to save memory). The default db backend 
is quick and scales well. Still, mysql tends to have problems with 
bigger text/blob fields: We occasionally see slow inserts in those 
bigger cache tables which handle page tables with ~0,5MB of html data 
per row and I've not found a way to change that on query, index or mysql 
config level. Additionally mysql (actually not mysql but more the 
underlying disks / storage systems) really gets problems with very high 
insert load (even if innodb is configured to speed up there at the cost 
of integrity) and in general mysql slows down if table space doesn't fit 
into memory anymore. These are points where other backends can be better 
suited, especially for caches.

Regards
Christian