[VESA] driver is extremely slow in vmware

[diver]

This is hrev56385 x86_64 in VMware Workstation 16.

Any resolution above 1024x768 makes screen updates extremely slow. Even at 1024x768 moving windows around uses 100% cpu but at least it is somewhat usable.

Installing vmware_addons and using included vmware graphics driver helps a lot.

Both at 1024x768 and 1920x1080 moving windows around uses only about 40% cpu.

[waddlesplash]

I believe this is a VMware bug; for me it happens with VMware Workstation 15 running atop Hyper-V but not when VMware uses its own hypervisor. Considering basically all other known setups with VESA do not have this problem, I don't think there is much we can reasonably do.

You can run a full-system profile and see if anything obvious comes up, but I suspect it's just buffer copying taking a very long time, which isn't something we really can do anything about.

[diver]

I just checked with framebuffer driver and it is also affected. Not only moving windows is slow but also apps start noticeably longer.

Somehow vmware driver fixes both of these things. Maybe something can be "borrowed" from it to fix the lagginess?

[waddlesplash]

The VMware driver behaves very differently from the VESA one on many levels, I don't know if that's reasonable.

[diver]

Any idea why graphics driver could affect application startup time?

[waddlesplash]

Try the profiler?

[diver]

Sure, I can try to do that. What are the steps to do that?

[waddlesplash]

profile -a -f -S while reproducing the issue should do the trick, then Ctrl+C it when finished and upload the output.

[diver]

Do I need to move windows around or start a few apps?

[waddlesplash]

Whatever you need to do to reproduce the issue.