Enable Intel FlexRAN with CPU C6 State on a Nodepool Virtual Machine

Products

• VMware Telco Cloud Platform RAN

Issue/Introduction

This article provides the prerequisites and procedure to enable Intel FlexRAN with CPU C6 state on a Nodepool VM.

Environment

4.0

Resolution

Intel Package C-State C6 is supported in TCP-RAN 4.0.

Pre-requisites

• Telco Cloud Automation: 3.1.0.23586009 or later
• BYOI: 23561559 or later
• Server: Dell XR11, 64 Icelake CPU(s) Intel(R) Xeon(R) Gold 6338N, 512 GB memory
• ESXi: 8.0.2 23424722 (Hot Patch build with C6 State support) or later

Follow the steps below to enable C6 state in a Nodepool virtual machine.

1. In TCA 3.1.0, create a nodepool VM from the given BYOI template (photon-5-kube-v1.28.4-vmware.1).
2. Instantiate the CNF (Here testnf is used as an example):
   
   1. Modify the CSAR to enable C6 State from the TCA UI go to Catalog > Network Function
   2. Select a Network Function, click on the 3 dots and select Edit.
   3. In the Infrastructure Requirements section expand Kernel Arguments and make the following changes:
      Remove idle=halt
      Change intel_idle.max_cstate to 6
      Add cpuidle.off=0 
         
   4. Create a text file (e.g. testnf-c6-tuned.conf) with the following contents:
      

      #Enable C6 State
      [cpu]
      force_latency=-

   5. Go to the Resources section and upload the text file to Artifacts/scripts/ and save as /usr/lib/tuned/c6/tuned.conf               
   6. Once uploaded, set the Tuned Profiles under Infrastructure Requirements to realtime,c6.                                                                                                                       
   7. Also make sure NUMA Alignment is set to Yes
      
   8. Save the testnf CSAR by selecting either Update Package or Save as New.
3. Instantiate the Network Function with the newly updated NF CSAR.
4. After the Network Function has been instantiated, the virtual machine’s Advanced Parameters should show the cpuid.5.0.edx attribute.
5. Running turbostat on the VM shows C6 is enabled: