Sequencer hangs up: Possible dispatcher overload

[StarFlea]

Hi Robin,

SharpCap hung several times during an evening of observing at the start of relatively simple sequences.
A restart brought no improvement.
The log file mentions a "Possible dispatcher overload"...

An example as attachment...

Cheers!
StarFlea

[admin]

Hi,

as far as I can see, SharpCap stopped responding to the keyboard/mouse and stopped updating the display at roughly the moment you started the final sequence (the one with capture 10000 frames after a prompt). The 'overload' warning goes along with stopping responding - basically it's recording that there are 63 things that it needs to do to update the UI and process input and nothing has been processed for 5s.

Unfortunately the log cuts off once it gets to the warning about not responding for 10s, so no idea if it comes back to life and no diagnostic info either

Can you try the same sequences using 'Test camera 2 (High Speed)' - I am just wondering if it is something odd perhaps in the webcam driver for the veLOX178C camera that is causing this - I have tested the same script with a PlayerOne IMX462 and had no issues.

cheers,

Robin

[StarFlea]

Hi,

unfortunately I can't reproduce the behavior with the test cam, but I've now attached a few logs from which you might be able to get some more information. All document the same type of hang at the start of a sequence...

cheers,
StarFlea

[admin]

Hi,

OK, those logs point to the problem - it looks like the graphics layer that SharpCap uses for display is freezing up. The key to that (for anyone coming here later and looking in their own logs) is finding this entry in the log

Code: Select all

at System.Windows.Media.Composition.DUCE+Channel.SyncFlush()

In this case, the underlying framework that SharpCap uses for graphics has requested a display update and the system has frozen trying to do it.

The two options here are

* Update your graphics card drivers to the latest version (from Intel/Nvidia/AMD - depending on graphics device type) and then make sure the 'Use graphics card acceleration' option in the settings is on

* Alternatively, turn *off* the setting to use graphics card acceleration in the settings and restart.

I am trying to find a better solution for this issue, but since it is not happening in SharpCap code, it's hard to deal with unless i can find a way to break it repeatedly on my system here

cheers,

Robin

[StarFlea]

Ah, understand, thx!

However, it's not entirely clear to me which of my GPUs SharpCap uses. The Windows Device Manager shows me an onboard Intel UHD and a dedicated NVIDIA GeForce GTX1660 Ti.

However, both drivers are up to date. What are the effects of disabling graphics acceleration in SharpCap?

StarFlea

[StarFlea]

When I look at the logs, SharpCap only seems to use the Intel UHD. I tried to explicitly assign the GeForce in the Windows settings, but according to the log, SharpCap remains with the Intel UHD:
Info 22:03:03.027571 #12 Graphics Card: Intel(R) UHD Graphics, v31.0.101.2121

Is there any chance of changing this?

[admin]

Hi,

I don't have control over the GPU used - as far as I am aware the whole display switches between the two, rather than some apps using one and some using the other. I'm not even sure if the log information is accurate in the case of two video controllers - SharpCap only records the first video controller listed by the system in the log (fine for 99% of PCs).

Switching to the software only rendering will bump up the CPU usage a bit (when using high speed cameras), as some work is transferred back to the CPU rather than being put on the GPU.

cheers,

Robin