in this rare instance oogle is your freind  Dorian though i still think you
would be better off with first 3 commands i gave you

n your case lsof does not need to check the GVFS file systems so you can exclude the stat() calls on them using the -e option (or you can just ignore the waring):

lsof -e /run/user/1000/gvfs

or you could kill the process like Ereo said that would proberly work as well and maybe better you will find all your process in systems monitor
carfull how you go with it though look around by all means but dont mess with it
its like windows yuk task manager  and the tab your looking for is you guessed it               processes

have a good evening dorian from blighty

kind regards colin