CEF Forum

Hi all,
I'm running into an issue where I get a graphics stutter - a frame that takes ~50 ms to render, instead of the usual 1 ms or so.

I've tracked the cause down to audio capture of the browser.
When I return true from GetAudioParameters() to enable audio stream capture, then anywhere from 200 ms to 2.5 seconds after initiating capture, the application stutters, with a single frame that takes > 50 ms to render.

From previous experience, this type of graphics stutter is caused by the nvidia OpenGL drivers being blocked when trying to allocate or free memory, due to excessive memory alloc/frees on some other thread.

It's possible also some threading priority issue.

The stutter is relatively reliably reproduced - it happens maybe 80% of the time after initiating audio capture.

When I return false from GetAudioParameters(), no such stutter is caused.

For context, I'm using offscreen rendering in an OpenGL app, on Windows 10, GPU is RTX 3080. CEF build is 4951, built from source.

Any ideas / thoughts / workarounds?

Possibly related to https://bitbucket.org/chromiumembedded/ ... acket-loss

amaitland wrote:Possibly related to https://bitbucket.org/chromiumembedded/ ... acket-loss

Possibly, however it looks like the proposed change in that thread was committed to Chromium already: https://chromium.googlesource.com/chrom ... %5E%21/#F1

That's the only performance issue I'm aware of.

Have you confirmed the change is included in your local build?

amaitland wrote:Have you confirmed the change is included in your local build?

Yes, the change is in my local chromium src.

- Load chrome://gpu in a CefBrowser instance, confirm GPU acceleration is enabled
- Try with an official spotify build, make sure it's not something specific to your source build.

amaitland wrote:- Load chrome://gpu in a CefBrowser instance, confirm GPU acceleration is enabled

The issue happens with GPU acceleration, and also without (e.g. using --disable-gpu and --disable-gpu-compositing")

amaitland wrote:- Try with an official spotify build, make sure it's not something specific to your source build.

Tried with latest spotify build, same problem.

Are you using release builds? Antivirus disabled?

Does the problem reproduce with different hardware?

Perhaps Marshall has some other suggestions.

You could try the Chromium profiling tools, to see if that points to a possible culprit. https://chromium.googlesource.com/chrom ... troduction