[Cog 3345] Too high cpu usage

[Gniiiii]

Describe
On my M2 Macbook Air, I noticed that Cog uses around 20% CPU when playing, which I find quite high for MP3 playing (winamp was taking less on less powerful CPU 25 years ago and HD video play-back is also using less).
Not playing, it is around 5%.
I'm not short of CPU time, but I'm concerned about the battery impact.

Expected behavior
I think less than 5% CPU usage can be expected during playback, and some 0.x % when not playing.

Version information:*

• macOS version: 15.6.1
• Cog version: ... Cog 3345

Additional context
around 2k titles in my library.

[kode54]

Disable the visualizer by removing it from the toolbar.

[Gniiiii]

It's already no in. My toolbar has this layout: (icons only)
[ file tree | info inspector | playback control | volume | speed | space | current time | position | shuffle | repeat | space | search | space | mini mode ]

I have no other Cog window open (expect the preference one when I did the experiments below)

I just played a bit with the setting "Use 3D rendered spectrum" and "Use flat perspective in toolbar", and it seems to have small impact (with both inactive, it seems to lower by a couple of %), even though nothing is displayed in any case.

I'm using the Activity monitor to get the load indication so the measures are somewhat empirical.
I also had a look at a sample from the Activity monitor too and I saw there was many threads but nearly all of them waiting for semaphores or mach events, nothing looking running wild.
over a 1.556s sample, I saw:
92ms spent in [DSPEqualizerNove process] -> deactivating the equaliser removes around 3% of CPU usage
53ms spent in [VisualizationNode threadEntry: ] other than waiting on a semaphore.
25ms spent in [ConcerterNode process] (with 9ms in vpoly0)
15ms spent in [DSPFaderNode process] -> (Just name guessing) I don't think I'm using a fader option, though.
Then, since there is a number of dispatch queues / worker threads, it could be small overheads adding up, maybe fostered by spurious wake-ups.

[mag01]

Yes, on my old MacBook Air (2013, Intel Ivy Bridge, 2 cores, 4 threads) it utilizes about 23% CPU when playing FLAC files.
I don't keep a collection of old Cog builds, but when trying some older builds from https://cog.losno.co/#older :

• 2405 (June 23rd 2022): ~7% CPU
• 3343 (October 9th 2025) and all later builds: ~23% CPU

Using the same settings and visualizer off in all cases.

[kode54]

Disable Rubberband, the biggest CPU usage contender, likely using 56% of the total time that Cog is consuming. This may be performed by setting the processing engine to Disabled.

Second, if it's still enabled, disable the 3D visualizer and use the 2D one instead, if at all. This will cut remaining CPU usage significantly as well. Unfortunately, no matter how simple the view may be, SceneKit is a CPU hog.

With both RubberBand and Visualizations disabled entirely, the remaining CPU usage should be in the order of approximately 15% of a core, or maybe 0.7% of the whole CPU, depending on how many cores you have.

To reduce this further would require complex work on the code. If you may look at it with Instruments and CPU Profiler, you'll see that from the remaining 15% of a core (M4 Pro), less than 15% of that 15% is being spent on the audio processing and output threads. The remainder is entirely the user interface code, mainly the timers updating the seekbar and time text display 5 times per second, and any other maintenance timers running. None of them are on significantly high intervals.

You could try the mini UI instead, though the seekbar and time position text are still being timed to refresh 5 times per second.

[mag01]

I have Rubber Band already disabled. I also tried removing pretty much everything from the toolbar except for the playback controls, but couldn't get lower than 21% (of a core). Seekbar (Position) and Current Time didn't make much difference.

Not sure where does the difference when compared to the older build 2405 come from.

[kode54]

That old build would also be Intel only, so it's running under Rosetta 2.