I'm following up on this post regarding network speed testing using iPerf3 to test the connection speed between a desktop PC and a dock-connected MS Surface Pro 4 (so it's connected to gigabit ethernet), both running Windows 10 and both showing truly abysmal speeds in things like copying files/folders between machines.
After disabling AV and anti-malware on both machines, I tested again and found that the speed in either direction using iPerf3 was never more than about 600Mbps, though file copying from the desktop PC to the SP4 reported speeds of less than 1Mbps, which was a serious concern. Oddly enough, file operations between each of the PCs and my QNAP NAS are at least 70MB/s so the woeful PC-to-PC performance is a surprise.
As suggested by someone in my previous post on this subject, I installed Ubuntu and iPerf3 on a couple of bootable USB thumb drives and booted both PCs with them. iPerf3 speed testing shows around 950 Mbps in either direction between the desktop and SP4, so that discounts any hardware issues.
The above must mean that Windows 10 must have really poor inter-PC networking, but if so then I'm at a loss to know what to do about it. The performance is so bad that it's much quicker for me to copy my files from the desktop PC to a folder on the NAS, then copy those files from the NAS to my SP4 - copying directly between those two PCs is excruciatingly slow otherwise.
Has anyone else encountered similar issues with Windows 10 PC-to-PC networking?