I currently have a database server with around 100+ databases on it. The number of databases grows on a weekly basis. Except for one control database, all of the databases contain only compressed (read only) MyISAM tables. Those databases are updated at most weekly (and most are updated every quarter).
My understanding is that, with replication, the compressed tables will end up as uncompressed MyISAM tables on the slaves, which isn’t the worst thing in the world, but having them compressed gives me much better performance, and allows me to keep the varchar()s in the table definition (and have them vary from database to database) without performance hits (although I suppose I could just set all of the tables to have fixed-length rows, but the compressing would likely reduce the size of the tables over that).
I can imagine replicating only the single control database, but since I only want to write to the master version of that, the replication would only be for reporting and backup, which is a relatively small load on the database compared to the writes it takes.
So I’ve been thinking about just using scp to get the database directories from the master to the slaves, and probably using MySQL’s replication to do the control database for the backup benefits only.
Any other ideas?