Did you check permissions on the var directory and its sub directories ? Did you check the ViewCaching setting in site.ini and others cache related settings (*Cache) ?
By default, UsePersistentConnection is disabled, I don't if this settings has good (or bad) effects on performance.
Perhaps you can set DebugOuput to enabled and paste here the result ?
Will this solve the problem of the long long time (30-40 sec) the system takes to edit or save an article (or any other object), even its content is short ?
Pascal
Ce qui embellit le désert c'est qu'il cache un puits... quelque part... (A. de Saint-Exupéry) - http://luxpopuli.fr/eZ-Publish