Unable to boot KVM VPS in SolusVM: cannot set up guest memory 'pc.ram': Cannot allocate memory

Symptoms 

• KVM VPS does not start in SolusVM - VPS stays offline

• When Rebooting VPS with debug at SolusVM > Virtual Servers > VPS > Reboot(Debug) the following error is displayed:

  SVM_ERROR: qemu-kvm: cannot set up guest memory 'pc.ram': Cannot allocate memory

Cause

This means there is not enough free memory on the node.

Resolution

1. Connect to the node via SSH
2. Free up cached memory:

   # sync; echo 3 > /proc/sys/vm/drop_caches

If the solution does not help add RAM on the node.