mac browser frames rate is eractic - VCS

[UnitRadius]

Hello,

When I run VCS Atari 2600 code (samples, my code, finished game ROM's, etcetera) the frame rate slows down and speeds up randomly.

This happens on Mac M1 Air - Sonoma 14.7.1 - Safari and Chrome.
It worked fine for me, for over a year, thinking some Apple update broke it.

Any idea how I fix that?

Thanks.

[sehugg]

Not sure, it has worked pretty well on my M1. Sometimes having dev tools open affects performance. Is an external monitor connected?

[UnitRadius]

worked great on my M1 also, not using external monitor, seemed like Sequoia broke it, maybe I should try Tahoe?
not sure what JAVA version to use, have latest Sequoia allows but Oracle has a much newer version

[sehugg]

I'm not sure what's up, Java is not a dependency though. Maybe try the Stellerator emulator or other platforms and see if the same problem occurs? Could be RAM pressure on your system too.

[fredsa]

A few lines of investigation:

1. When it's slow/sluggish, try ⋮ (top right) > More tools > Task manager, then for the IDE tab:
   • How much memory is being used?
   • What is the CPU % at?
2. Open macOS' Activity Monitor
   • Are there any/several consistently high (>90%) CPU processes on your machine?
3. Is the frame rate always variable or sluggish?
4. If you close tab and then reopen (CMD-SHIFT-T), does the issue go away?
   • I have seen very long running sessions become sluggish. By very long, I mean I leave the IDE open and running whatever I was working in a tab for > 24 hours. Closing the tab and reopening it brings back the performance instantly. I haven't bothered to investigate, but I'm guessing high memory usage or maybe memory fragmentation.
5. If you close the browser (CMD-Q) and restart, does the issue go away?

As a data point, I'll add:

• I'm on a M1, recently moved to Tahoe 26.3.1, using Chrome. Ignoring the odd >24 hour use case I mentioned above, I find that the IDE is always blazingly fast.

[UnitRadius]

Thanks. I found a solution that works for me. I installed MacOS Microsoft Edge browser. It does not use Apple Webkit and works perfectly.

[fredsa]

Great that you have a workaround.

To confirm:

• Are you still (consistently) seeing variable/sluggish frame rate with Safari and Chrome?
• Is the issue only with VCS Atari 2600? Are (some of) the other platforms obviously better? Or same issues there?

[UnitRadius]

Yes it starts out fine, then slows down. I tried all browsers available on Mac App Store. Then I heard about MacOS Edge. Is only on MS site because Apple requires other browsers in App Store to use WebKit.

I was only using it on Safari/Chrome/Firefox/DuckDuck for 2600, and the game I was playing used SuperBank 128k ROM.

Have not updated to Tahoe. Did all the updates to previous OS version.

Will try some other platforms.

[sehugg]

I have seen on Safari that the timers (both setTimeout() and requestAnimationFrame()) are limited to 30 FPS in Low Power Mode, and there's no workaround that I can see. But I haven't seen this on other Mac browsers.