SolusVM: Cannot Allocate Memory Error – Best fix ?

Are you facing SolusVM: Cannot Allocate Memory Error ? This guide will help resolve it.

A few days ago, one of our customers came across a "cannot allocate memory" error. This generally happens while we boot KVM VPS in SolusVM.

Here at IbmiMedia, as part of our Server Management Services, we regularly help our Customers to perform related SolusVM queries.

In this context, we shall look into methods to resolve this SolusVM error.

Nature of SolusVM: Cannot Allocate Memory Error  ?

It is quite common that users experience that they are unable to boot KVM VPS in SolusVM.

In such situations, we often notice that the KVM VPS does not start in SolusVM – VPS stays offline.

In addition, we come across either of the below errors, if we press the Reboot (Debug) button on the page, SolusVM > Virtual Servers > the affected VPS:

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


Domain kvm101 has been undefined
Domain kvm101 defined from /home/kvm/kvm101/kvm101.xml
Domain kvm101 marked as autostarted
error: Failed to create domain from /home/kvm/kvm101/kvm101.xml
error: internal error: qemu unexpectedly closed the monitor: ioctl(KVM_CREATE_VM) failed: 12 Cannot allocate memory
2021-03-23T08:56:18.128294Z qemu-kvm: failed to initialize KVM: Cannot allocate memory

These errors mean we do not have enough memory on the node. This can be due to cache.

Often, it is quite possible that there is a lot of cached memory on the KVM Slave.

How to fix SolusVM: Cannot Allocate Memory Error ?

The best solution here is to clear up the cached memory.

To do so, follow the steps outlined below:

1. Start by connecting to the node via SSH.

2. Then we free up the cached memory by running the below command:

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

Finally, if the above method does not help, then we add RAM to the node.

[Need help in Server Memory Error? We are here. ]


This article covers the best way to tackle SolusVM: Cannot Allocate Memory Error. In fact, this error happens while booting KVM VPS in SolusVM. This error signifies that there is not enough free memory on the node.