Noisy QPC2 machine

[pjw]

Of course, its difficult to get a PC-side snap of whats going on in QPC2 full screen mode, so this is the best I could do. Its a bit on the low side compared with normal misbehaviour, which shows about 50-54%. I hope it tells you something..

[mk79]

Hm, difficult to tell without symbols. But please click the "Stack" button on the CPU thread and show the result. And perhaps 3 times to see how it differs over time

[Dave]

What happened when you checked all the files against a clean install? Maybe one of them had been modified to carry a payload?

[pjw]

Hm, difficult to tell without symbols. But please click the "Stack" button on the CPU thread and show the result. And perhaps 3 times to see how it differs over time

min 09
QPC2.exe+0x1a6c5
QPC2.exe+0x23f0a
QPC2.exe+0x23f94
QPC2.exe+0x1a6c5
QPC2.exe+0x1d56b
QPC2.exe+0x19a65
QPC2.exe+0xc9af
QPC2.exe+0x23f0a
QPC2.exe+0x23f94
ntdll.dll!RtlInitializeExceptionChain+0x36
QPC2.exe+0x23f30

15
QPC2.exe+0x1d5d7
QPC2.exe+0x19a65
QPC2.exe+0x1d5d7
QPC2.exe+0x19a65
QPC2.exe+0xc9af
QPC2.exe+0x23f0a
QPC2.exe+0x23f94
ntdll.dll!RtlInitializeExceptionChain+0x36
QPC2.exe+0x23f30

19
QPC2.exe+0x1dad1
QPC2.exe+0x19a65
QPC2.exe+0x1dad1
QPC2.exe+0x19a65
QPC2.exe+0xc9af
QPC2.exe+0x23f0a
QPC2.exe+0x23f94
ntdll.dll!RtlInitializeExceptionChain+0x36
QPC2.exe+0x23f30

[pjw]

What happened when you checked all the files against a clean install? Maybe one of them had been modified to carry a payload?

Nope, its not that. I did a clean install to another folder. Started up a blank instance (no boot). Same same.

[mk79]

I think I now know what's going on. Later Windows versions apparently started to send mouse messages to the window the mouse is in even if the mouse hasn't moved. The mouse messages however are one of the criteria that prohibit QPC from sleeping. And as you're using QPC in fullscreen mode the mouse is always in the window... I guess if you switch to windowed mode and move the mouse to another application the CPU utilization will cease.

The fix is pretty easy, but the QPC2 v4 line is dead. I have rewritten large parts of QPC2 and there will be a QPC2 v5 eventually, but until then the fix will have to wait.

Cheers, Marcel

[pjw]

I think I now know what's going on. Later Windows versions apparently started to send mouse messages to the window the mouse is in even if the mouse hasn't moved. The mouse messages however are one of the criteria that prohibit QPC from sleeping. And as you're using QPC in fullscreen mode the mouse is always in the window... I guess if you switch to windowed mode and move the mouse to another application the CPU utilization will cease.

Well done! Thanks!

The fix is pretty easy, but the QPC2 v4 line is dead. I have rewritten large parts of QPC2 and there will be a QPC2 v5 eventually, but until then the fix will have to wait.

I can live with that (provided I can hold my breath that long.. )