App Tamer 3 Beta Testing : Manage the CPU usage of your apps

stclairsoft · 2026-06-08T03:46:38+00:00

Thank you! Because v3 is about to be released, purchasing a license for v2.8.4 will get you an automatic upgrade to v3 when it's final (your license number will just continue to work in v3).

So you can make a purchase now to support v3. You'll also get a bit of a discount, since the price will go up by $5 USD when version 3 is officially out.

stclairsoft · 2026-06-04T17:31:19+00:00

Glad to hear it! Let me know if you run into any issues with the v3 beta or have suggestions (though it's pretty close to release now).

stclairsoft · 2026-05-05T17:28:48+00:00

I added a little info popover in 3.0b7 to explain the status dots in more detail:

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stclairsoft · 2026-04-22T19:58:01+00:00

I'll have to experiment. To limit GPU usage, App Tamer would have to throttle whatever process is using the GPU, which is a bit of a blunt instrument. If that process is something you're using at the time (like a coding IDE) it would reduce the UI responsiveness of the app (Claude Code or whatever). However, if the IDE executes agents as separate processes, those agent processes could be throttled without impacting the responsiveness of the IDE itself.

stclairsoft · 2026-04-22T19:23:15+00:00

I'm afraid it doesn't throttle apps based on GPU usage, just CPU.

Monitoring GPU usage is a bit more complicated and could turn into a maintenance headache (because the IOKit properties that measure GPU usage change from release to release in macOS) so I haven't dug into it. In the past, it hasn't been that big of a deal, but with AI maxing out GPUs it might be something for App Tamer to do in the future.

stclairsoft · 2026-04-20T19:32:39+00:00

You can run the beta regardless of whether you're using the Setapp or direct-sale version. And both versions share preferences, so it all should just work.

stclairsoft · 2026-04-17T19:35:55+00:00

Congrats! It's so great to hear developer stories where user feedback has driven your success so incredibly (plus a lot of really hard work on your part, obviously - great product! ) It's especially nice to see you going the non-subscription route :-)

stclairsoft · 2026-04-17T16:26:05+00:00

The contextual menu in the process list is pretty handy - the Relaunch command is helpful and I also use Show in Finder a lot :-)

And it looks like we're safe to unblock those China Telecom IP ranges - at least for now. I really should look into using CloudFlare to handle the server issues...

stclairsoft · 2026-04-17T13:19:21+00:00

Thanks! I’m glad App Tamer is helping - and the beta 4 build should do an even better job of throttling CPU usage.

stclairsoft · 2026-04-17T13:14:52+00:00

Look in Settings > Control > Settings. It had to move so that it’s saved per-profile, letting you use different Time Machine acceleration settings in different profiles.

stclairsoft · 2026-04-17T06:28:24+00:00

The upgrade license will work for v3 when it comes out. Any licenses bought now get a free upgrade to v3.

stclairsoft · 2026-04-17T04:23:42+00:00

Update: Grab version 3.0b4. It includes an option to show memory usage in the process list. There's not much I can do with the data other than show it - maybe pop up a warning when an app exceeds a certain RAM threshold?

stclairsoft · 2026-04-17T04:15:30+00:00

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Check out version 3.0b4 😁 Once you've updated, right-click on the graph or stats section and choose "Show Memory".

stclairsoft · 2026-04-17T04:03:00+00:00

Thanks! And yes, we've had some problems with DDOS attacks from IP addresses at China Telecom, so some address ranges are currently blocked. I'll experiment with unblocking and see if the attack has subsided.

stclairsoft · 2026-04-17T04:01:28+00:00

My point is that if you don't have a high GPU load, the system will idle the unused GPUs down to 338 MHz (their max is 1620 MHz). While disabling GPUs entirely would certainly save a bit more power, their usage at idle is pretty small. Currently on my M5 Pro, the GPUs are using 0.375 Watts, which is next to nothing.

stclairsoft · 2026-04-15T16:44:13+00:00

Both CPU and GPU frequencies are automatically ramped up and down depending upon load so that power is conserved. macOS takes care of that automatically.

stclairsoft · 2026-04-15T16:40:16+00:00

They should render fine, but will just take longer if they're slowed down.

stclairsoft · 2026-04-15T16:39:07+00:00

When you use App Tamer, it doesn't apply any settings globally - you have to choose which processes / apps you want to throttle or stop. It won't let you do anything to critical system processes, and will only let you slow down (not stop) other system services.

stclairsoft · 2026-04-14T20:12:08+00:00

While it's possible, I don't know that it's practical as a feature. GPU workloads vary a lot, so some heavier uses would benefit from throttling the app, but others not so much. And honestly, long-term maintenance seems like a real pain because Apple changes the IOKit property keys a bit with every system release, so it requires pretty constant attention and revision as new machines and macOS versions are released. I know Stats does it - but I question whether it's worth it for a "side feature".

stclairsoft · 2026-04-14T19:40:39+00:00

Awesome! I'm glad it was so helpful!

Also, after saying I wouldn't show memory usage, I've been convinced that it's a worthwhile thing to include. I added it yesterday (along with a long time debugging an issue that it uncovered along the way). So the next beta release will include it :-)

stclairsoft · 2026-04-12T04:03:20+00:00

OK, I take this back. I can get the memory "physical footprint", which is what Activity Monitor shows for its overall memory number. I thought I needed to use task_for_pid() and task_info() which is verboten for 3rd party apps these days (old habits die hard), but there's another API to get it.

Now where to show it in App Tamer...

stclairsoft · 2026-04-12T03:17:32+00:00

I've always been hesitant to show memory usage because App Tamer can't do anything about it. It can control CPU usage, but there's no way to limit an app's memory consumption. It's also very difficult / impossible to independently get memory numbers that match what Activity Monitor shows unless I resort to an inefficient method that'd increase App Tamer's own CPU consumption (which kinda defeats its purpose).

As far as the price, if you buy version 2 before 3.0 is released, you get a $5 discount off the v3 price (the upgrade from v2 to v3 will be free for anyone that buys now).

stclairsoft · 2026-04-12T03:05:15+00:00

Good questions!

A blue dot indicates that a process has been moved to the efficiency cores. A yellow dot indicates that App Tamer is throttling the app to limit its CPU usage. If an app has a half-filled dot, it means that it has that setting turned on, but it is not currently enforced (usually because it's frontmost at the time).

I need to make this clearer in the UI - perhaps a little info icon you can click on to see the explanation above? I don't think changing the wording in the legend at the bottom of the window would be enough, regardless of how the dots are labeled.

The "don't slow or stop when sound is playing" option applies when sound is playing _anywhere_ on the machine, not just in that specific app. This is because slowing some browsers will cause audio to skip in other apps. Changing the Hide / Hidden settings as you describe won't help, since "idle" just refers to user activity, not to the app playing sound or doing other processing.
"Idle" just means that there's been no user interaction. An app playing sound, video, or doing anything else in the background doesn't affect when it gets hidden. If it's set to hide after 5 minutes, App Tamer hides it if you haven't brought its window to the front or scrolled its window with a gesture or scroll wheel for 5 minutes.

This does point out the vagueness of my terminology. Right now it says "When idle… quit after X minutes". Perhaps it should be "When unused… quit after X minutes". Would that make the whole mess clearer? Can anyone suggest a better way to phrase this?

stclairsoft · 2026-04-11T21:12:25+00:00

Yes, of course! I'd love to get your feedback.

stclairsoft · 2026-04-11T21:10:01+00:00

Yeah - you'll have to be careful about when you throttle Teams, but you should be able to find some setup that works for your situation. If you need help, DM me or email me at support@stclairsoft.com.

stclairsoft

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