VMware vSphere ESXi 6.0
VMware vSphere ESXi 6.5
VMware vSphere ESXi 7.0
NFC is single threaded - performance will always be limited by this and you will never move faster than the single thread.
NFC is encrypted - you can speed up by disabling SSL and improving the the speed up to 20%, this comes at the expense of security and might not be an option for most environments.
NFC is synchronous - we must READ/WRITE/CHECK then proceed.
NFC can only do one operation at a time READ/WRITE/CHECK.
NFC is latency aware - it will throttle when latency transitions are seen.
• The provisioning TCP/IP stack can be enabled and configured on the ESXi host for some additional performance https://docs.vmware.com/en/VMware-vSphere/7.0/com.vmware.vsphere.vcenterhost.doc/GUID-AC418F24-8E7D-40B6-9D07-A9DB504C7F1B.html
• You can disable SSL with the KB https://knowledge.broadcom.com/external/article?legacyId=2056830
• Avoid using NFC for any deployment or movement of large files where speed is a priority.
Impact/Risks:
NFC's performance-limiting factors prevent it from being used to rapidly deploy VMs across non-shared storage.