akonadi services and mysqld use too much memory in kubuntu 16.04

Until ubuntu provides a fix for this problem, i found a workaround!

I use the command pkill -f akonadi and add it to the startup. System Settings>>Startup & Shutdown>>Autostart. using this command all the akonadi services get killed at startup and mysqld process will be killed along with it and all the memory occupied by them will be released.

after this everything works normally and i found no errors or missfunctionalities whatsoever.

Removing akonadi services

Using command sudo apt-get remove --purge kmail akonadi-server you can uninstall akonadi-server and all it's integrated services without any harmful changes to the system. this way memory usage goes under 500MB and mysqld won't run and take resources.

I had the same problem, and although I don't know how to uninstall akonadi, I uninstalled the applications that make usage of it: kontact, kaddressbook, kmail, knotes and korganizer. Akregator doesn't seem to start akonadi so I let it installed.

sudo apt-get remove kontact kaddressbook kmail knotes korganizer

My memory usage had decreased from almost 900MiB to less than 500MiB after the startup thanks to akonadi not being started. As akonadi is not started, neither it is that mysqld process that ends wasting more than 800MiB after a while (making a total memory usage of 1.5GiB with no any other program running).

If you don't want to uninstall this applications, you can close them all from the system tray. In my case there were running kmail and korganizer. In the case of korganizer, you have to uncheck the option of reminding events from its icon in the system tray (I think it appears as events reminder daemon, or something similar). This way, next time you boot the computer, this processes won't be initialized and akonadi won't be started.

But be aware, starting any of this applications just once will start akonadi until you shut down the computer, it's not killed when you close the application (note: you can stop it from the terminal with 'akonadictl stop').

If you want to disable the services instead of removing them to avoid future dependency issues, You can just disable them by editing the configuration file.

To disable the server, edit the akonadi server configuration file at ~/.config/akonadi/akonadiserverrc.

Change StartServer=true to StartServer=false.