By default, ThunderX2 systems are shipped with 4-way Symmetric Multi Processing (SMP). Some workloads can benefit from reducing or eliminating SMP threading within the CPU/core. Below is how this can be managed to suit the workload needs.
1) Access the system via console.
2) Press ESC key to enter BIOS setup
3) Select the Chipset tab in BIOS
4) Select 'Symmetric Multi-Threading' option
5) Choose the threading model desired
6) Save BIOS settings and reboot the system
At this point the system will reflect the choice you made and SMP will be altered.
NOTE: Altering SMP will reflect in a change in core count seen in Linux.