High CPU Usage When Stopped

edited October 2021 in Bug Reports

I’ve noticed that the CPU meter shows higher usage when the project isn’t playing versus when it is. I might even have noticed that CPU usage goes up (instead of down) when I mute audio units on a channel.

PS Could NanoStudio 2 be programmed to not use CPU for effects and channels that are muted? I think it’s called “smart disable” in Reaper or FL Studio (can’t remember which),


  • edited October 2021

    @Lerolightning - it's important to understand how CPU metering in iOS works. It's very different than on a PC.

    It is not a reflection of the percentage of total CPU power is being used. It's a reflection of the percentage of CPU power that iOS has allocated at the time.

    iOS dynamically allocates resources as needed, and it will scale them back to conserve battery when it thinks there is less demand. If it does this because it doesn't need to work as hard then the CPU % shown can actually go higher even though the device is doing less. A higher CPU % reading isn't necessarily an indication of higher work at all. Weird - I know - but that is the way it is.

    There is no way on iOS for a programmer to control this allocation, and no way to meter absolute usage percentage. Furthermore, the OS has less ability to smoothly disable or unload and reload plugins than PCs do. Most of those tricks that are easier on a PC are very problematic on iOS.

    Generally, it's better not to pay a lot of attention to the CPU meter other than as a general indication of when you're really pushing things. In the end, the only reliable indication of too much load is when you start to get drop-outs in the audio, and/or sluggish UI behavior. Other than that, there's no point in overly focusing on it.

  • @number37, Thanks for the great explanation. I really appreciate it.

  • You're welcome. It's a question that comes up often as people get into iOS from desktop.

Sign In or Register to comment.