Windows USB latency too high - USB device connects but does not work properly

R

RyanA5

Bit poster
I don't have a Windows Machine, so Im running a virtual one with Parallels. All I need it for is to run a power monitor driver/program to display the current current draw of my embedded device. The issue is that the latency of the USB is so slow that > 90% of the USB packets are being dropped/not ACK'd fast enough. The power monitor is running ~10x too slow because of this. I don't see any questions about USB performance anywhere - it seems like others aren't having this problem or aren't doing what I'm doing.

Is there any way to debug/fix this in parallels? I need to run other programs on here too like STLink which uses a JTAG interface and I'm concerned that any hardware -> hardware connections are going to just break using parallels.

It's such a cool program I can't imagine that this is really going to make me have to return my license and buy a Windows laptop.
 
Hi @RyanA5 could you please provide us with app which you're using for checking the usb performance? Or may be provide us with the screenshot of USB performance issue. Thanks in advance.
 
Hi @Maria@Parallels , the app I'm using is called Power Tool by https://www.msoon.com/hvpm-software-download . I took two videos. Video 1: shows the power monitor tool working on a windows machine (not parallels). Video 2 shows it not working on parallels. To recognize the difference, look at the timestamp in video 2 where I hover my mouse over. You can see that every few seconds this gets further and further behind real time. Basically, it's not monitoring the power in real time - it must be dropping USB packets because the ACK is too slow.
 
They don't care hardware developers.. I asked similar questions in the past.. They even do not reply.. They only care Mac users that want to run a few Windows apps.. Who needs that I don't know.. Internet Explorer for the sites?

All the HID based debuggers, interfaces, composite devices seems to have the same problem.. VMware runs those devices well, however its graphics handling is not as fast as Parallels.. I tried USB servers without success..

That's why I stopped using Parallels, Mac's etc for hardware development.. Pity.. Buy a decent Windows laptop..
 
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