I have tried to use PHPMyAdmin to optimize. However, it doesn't seem to optimize the tables properly. The reason why I say that is after optimizing, I ran the script that I got from here https://premium.wpmudev.org/forums/topic/optimize-mass-databases, it still keep saying some tables need to be optimized.
I ran wp-optimize plugin and it seem to delete post revisions and optimize the tables but it is kinda tedious to do this blog by blog as it is not a global function and it register the original wp db instead of the blog's db.
Is there any script available that could be used?
I was using cronsh2 script at tamba to back up single installs with 1 DB. I am not sure if this script could be used to backup 256 DBs or whether it is appropriate to do so. How should I go about setting up a back up plan for 256 DBs?