We are facing a huge database growth as we send newsletters to a growing recipients list. The newsletter is sent with CiviCRM Mail to a contacts group. I realized that the biggest table in our project is the civicrm_activity_contact table - and I am quite sure that most of the entries are those entries generated when a contact received the newsletter.
As there is a tab "Mailings" for each contact where all these newsletter mailings are listed I wonder why there are activities created additionally? Is there a need for these activities? Can I turn off activity creation for mass mailings somewhere?