Re: [SM-DEVEL] multiple SQL servers

[Brian G. P. <br...@br...>]

On Monday 26 March 2007 08:58, Cor Bosman wrote:
> Hi all, ive been wondering what the best solution would be to balance
> the sql load over multiple mysql servers. Even though we are currently
> not hitting the limit of a single sql server, we're getting too close
> for comfort.

I've used all three approaches to 'clustering' for different applications 
over the years. For Squirrelmail, I'd recommend testing a MySQL Cluster 
solution first.

> - MySQL Cluster. 

  Your comment about 'everything is kept in memory' isn't quite true.  The 
running fragments are kept in memory, but there is a asyncronous process 
to push data to disk.  Any reasonable UPS solution should be able to send 
the shutdown command, and MySQL will clean up and spool to disk.

> - MySQL Replication.

MySQL Replication can be very fast when the MySQL servers are on the same 
network segment and especially if they have a dedicated network interface 
to communicate over.  I suspect that your average write times would be 
fast enough to overcome any issues with network-based load-balancing of 
new connections.

> - Some homegrown partitioning of the tables, with some code in SM to
> select the correct SQL server.

I really wouldn't recommend doing a 'roll your own' approach until after 
you've tested the two methods that are supported by MySQL.

Regards,

   - Brian