I've recently upgraded my workstations to Windows 11, and now I'm facing a problem: the bandwidth to our SMB shares has dropped to about half of what it used to be. We have HP Z workstations equipped with Intel 10Gbps fiber cards, and while we usually achieve reads/writes of 800-1000MB/s with our Avid Nexis NAS, the speeds on multiple Synology NAS units and Editshare mounts have capped out at roughly 500MB/s. All of our workstations were configured from the same cloned image, so they're identical. Interestingly, we didn't have this issue with Windows 10. All machines are connected via the same switch. We've compared the NIC settings with some PCs still running Windows 10 that are functioning normally, and all settings match up. We do have another set of Z workstations on Windows 11 that still get 800-900MB/s, proving that it's possible with the same hardware. I'm starting to wonder if the image was built from a Z840 and migrated to a Z8 with slightly different architecture. Is there anything else I can check to resolve this?
1 Answer
It sounds like the SMB signing feature may be enabled by default in Windows 11, which can significantly increase CPU usage and lead to slowdowns in your network speeds. You might also want to check if SMB encryption is turned on, as it can affect performance as well, especially when handling high-speed connections. I recommend doing some testing with iperf2 to ensure you're hitting line speed between your server and workstation. Just a heads up, iperf3 isn't the best choice for Windows environments.
I tried this, but it didn’t improve anything. Are there any other Windows-compatible apps you'd suggest?