What is Numa in Microsoft Hyper-VOur customer had to deal with this kind of events every time this VM started up, so naturally I took a deep-dive in searching for a resolution for this issue. I have as many others heard of this NUMA (non-uniform memory access) as a neat feature for better performance of our virtual machines, but never thought of this feature having a bad impact to our VM’s.
The second hit was also technet site stating that you should resolve it by:
- Ensure that the memory associated with the VM is not larger than the memory associated with the NUMA node
- Set the preferred/required NUMA settings for each VM. These settings are exposed via the following properties in the Msvm_VirtualSystemSettingsData object in the WMI model: NumaNodeList and NumaNodesAreRequired
I found really great explanation on this great site written by “Benjamin Athawes” abound NUMA node boundaries for modern CPUs. Please do read all of it because it really explains the way to determine the NUMA boundaries of your host.
All this information states that I have 2 NUMA nodes with per node 8CPUs and 13Gb of RAM.
So knowing this I should not deploy VM with more than 13Gb RAM and 8 vCPUs.
The VM generating this error is equipped with 16Gb of RAM and that was causing this event, so it is very important knowing this limitation for deploying good performing VMs.
Solution in my case had 3 options:
So knowing this I should not deploy VM with more than 13Gb RAM and 8 vCPUs.
The VM generating this error is equipped with 16Gb of RAM and that was causing this event, so it is very important knowing this limitation for deploying good performing VMs.
Solution in my case had 3 options:
- Ignore the warning if you do not have any performance issue
- Limit this VM to NUMA boundary of in my case 13Gb
- Put in some extra memory to reach 16Gb per NUMA node (2 x 16Gb)
Nice Info . (h)
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