[TYPO3-english] How many sites can you run from one CMS?

[Muriel le Pair]

Hi,

Jigal van Hemert schreef op 08-01-14 13:38:
> On 8-1-2014 12:32, Steffen Gebert wrote:
>> Sure, it grows. But multiple installation would grow also. So the
>> question is more, what grows so fast.
>
> Probable candidates are:
>
> - cache tables. In some recent versions of TYPO3 there is a scheduler
> task available to remove old cache items. Depending on how quickly the
> tables grow you can run this more or less often to keep it clean.
>
> - history. If a lot of editing is done the history table can grow fast.
> There is also a scheduler task to remove old items (although that can
> limit the things you can roll back from the past if you remove history
> from a short time ago)
>
> - log. You can remove old items here too. In that case you can't look
> too far back to see what happened when, but that might not be a problem.
> This table can also grow rapidly if the logging level is rather low. If
> you made sure there were no problems during development (or on a special
> development installation) you can very well decide to not log warnings
> and notices.
>
> - deleted items. As you know, TYPO3 only marks items as deleted. In
> combination with the history you can un-delete items. You could remove
> deleted records which are modified a long time ago for the last time.
>
> Furthermore, databases need maintenance. Depending on the database
> engine you can execute ANALYSE TABLE and OPTIMIZE TABLE statements from
> time to time. This can optimize the space taken by deleted records and
> can optimize the table indexes.


Ok, thanks this all makes perfect sense.

But I'm still wandering about performance. What happens for instance if 
you clear all cache and 20 sites need to recache all there pages at the 
same time..

I am wandering about the performance of 1 huge database versus 20 
smaller databases. If the table indexes are all setup right, and if the 
queries are optimized it would not make very much difference.
But "TYPO3" tends to get all records and them do something with it 
("select * from table" instead of pulling the correct data in the first 
place).

And also I am wandering. Is it possible to separate them again?
So for instance can you quickly export all data from 1 domain in a 
multiple website installation to another database? Never really looked 
in to that.

--
kind regards,

Muriel le Pair