Ubuntu 16.04 does not have MySQL 5.5, it has 5.7. The most likely explanation for the memory usage going up is that default buffer sizes have been increased significantly for mysqld over the last few releases. You may need to edit config files to reduce the buffers.
** Package changed: mysql-5.5 (Ubuntu) => mysql-5.7 (Ubuntu) ** Changed in: mysql-5.7 (Ubuntu) Importance: Undecided => High ** Tags added: xenial -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1576930 Title: Excessive consumption RAM of mysqld daemon in Kubuntu 16.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mysql-5.7/+bug/1576930/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs