job is killed

[henrik]

my job consumes a lot of memory (almost consumes all of the system 
allowed ram).
when the job is running, it will have the chance to be killed.
I just got the reminder in terminal: Killed. and job exits.
who is killing my job? linux kernel, or VPS management program?
(I am using a 2 core, 8g RAM kvm vps).
Thank you.