I am trying to play Shank 2 and record with kazam but eventually the game lags way down and then kazam shuts down due to running out of memory. THere are a bunch of process's that are taking up a lot of VIRT ram per top. Here are some examples, can I just kill these process's?

knotify4
console-kit-daemon
xfce4-volumed
indicator-messa
xfce4-indicator
zeitgeist-datah
update-notifier
zeitgeist-daemo