Here are soem very necessary and import information for optimising mysql parameters. This may be helpful especially when aMember database grows more than a few thousand users/members. http://drupal.org/node/85768 Also applying indexes on each field helps.
To work with the tuning parameters of mysql, one does not need to get into the SSH Shell. I use the Navicat to analyse the variables and their states. The program is very cheap and its really really worth it: http://www.NaviCat.com
To users wanting to buy this product, I woud advice to wait for a few months until version 8.0 comes out. They have a price <> version policy and that means that you can get updates only for that version for free. If you buy now, then only for version 7.0 for a few months!!! So the version 8.0 is due and thereafter version 9.0 may come out after 12 - 18 months.