I like the flatfile structure esp. on my shared hosting platform.  I like how its all under my own account directory--no shared/separate sql server to worry about.  So how many messages would be too many for the flat-file format on a Unix server?   It looks like it stores a txt file for each thread in the Messages directory?  I know I probably won't get that busy, but at what point should SQL be considered?  15,000+ messages...50,000+?   Would 50,000+ small files in a Unix directory start to tax the machine in terms of file access times and/or load?   Anyway, I guess I could just use flat-file until my provider says something about it   
  Anyone know of the biggest (in terms of messages) eblah flat-file forum?  Thanks for any info!

for the biggest, see this. Those are the biggest we know of.. http://www.eblah.com/forum/m-1075526918/


For the question. The bigger the forum doesn't necessarily tax the server any more than a smaller forum because there are more/larger files. It's more dependant on the number of times and the frequency those are accessed.

So generally a large forum will be accessed more because it will be more popular. So i suppose the question is, how busy, rather than how large. And that's totally dependant on your hosts servers...

I've had complaints with TOS violation server overload in the subject line when i was getting around 10 connection requests per second going to my hosts server, when i was hosting spybot search and destroy updates. That was too much for my shared host.

I'm happy with the flat file version at the moment, but my forum isn't that large... When the SQL version is fully up, running and with a few versions under its belt i'll sure be upgrading. The forums speed especially busy forums should be increased massively. Hopefully...  

It depends.  It usually won't tax the server.  Older versions would tax the server a lot more than newer versions, as the database has been fixed up a little to make things quite quicker for small and large forums.