I'm connecting to a hard-wired system via Remote Desktop from my laptop to download a large folder from a VMware server and I noticed an unusual pattern in transfer speed. Speed seems to slow down drastically when WinSCP loses focus. For instance, moving folder with approximately 600GB in large files, transfer is initially set to complete in about 15 hours. Open another program in remote session (or even minimize remote desktop window to look at local system) and come back to transfer to find ETA has climbed to 1.5-2 days (up to 6 days at one point). Once WinSCP has focus this time drops back down to a reasonable estimate again within a few seconds. As far as speeds go, I minimized RDP to post this question. When I flipped back to RDP (WinSCP only program running on remote system so focus was technically never lost) I noticed speeds of around 1Mbps, but they quickly climbed back up to a little over 3Mbps.
I expect fluctuations based on network activity but I'm intentionally avoiding other bandwidth-intensive activities while these complete. All systems/equipment are using GBE for transfer and are all happening across an enterprise switch. Was just wondering if this slow-down is by design - if so, can it be modified to run at full-tilt whether or not window has focus (didn't see any options in preferences dialog)? Have not observed this behavior in older versions of WinSCP, but this is my first time using the queue to manage a large transfer. Thank you.