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I also recently discovered that something like 12% of CPU on my 2020 macbook air is used whenever I'm in a room with anything greater than perfect silence, by '

I also recently discovered that something like 12% of CPU on my 2020 macbook air is used whenever I'm in a room with anything greater than perfect silence, by 'coreaudiod', because it apparently is constantly listening to the microphone built in near the keyboard and spending cpu cycles trying to filter out background noise. Apparently running the signal desktop app in the background is enough to keep coreaudiod constantly wasting battery. Because signal is open and has been granted permissions for microphone and speakers, even if no call session is open? https://www.google.com/search?client=firefox-b-1-d&q=macos+coreaudiod+cpu+usage https://www.google.com/search?client=firefox-b-1-d&q=macos+c... meanwhile, "Slack Helper" is reporting 15% cpu usage just sitting there doing nothing. Imagine the cumulative kilowatt-hours wasted globally by all the CPU cycles spent by slack just to exist as basically a glorified IRC app. If you really want to see slack waste CPU and battery, leave a channel open that somebody has pasted a high FPS animated GIF into, in the slack window in the background. Easily 35% usage.

lostlogin 5y ago
> If you really want to see slack waste CPU and battery, leave a channel open that somebody has pasted a high FPS animated GIF into This is basically an attack especially if you post a couple of them. My god.
- fotta 5y ago
  I basically avoid large channels at work because it just absolutely bogs down my machine.
  - waspight 5y ago
    Just turning off animations in settings would help I guess
    - throwaway09223 5y ago
      connecting to slack from a third party application is even better.
- art0rz 5y ago
  It is really surprising how bad/slow Slack is compared to Discord
  - hansel_der 5y ago
    i assumed as much given one is made for gamers and the other for corporates.
kitsunesoba 5y ago
The coreaudiod issue might have to do with apps that use the mic "priming" it by keeping it active even when there's no call. Some chat apps do this to avoid the 1-2s delay associated with turning on the mic, so audio starts streaming as soon as the call starts.
- Kwpolska 5y ago
  Keeping the mic active when you’re in a call but have the mic muted is acceptable and understandable. At any other time, it would make me think the app is recording everything and shipping the recordings to the friendly neighborhood TLA agent. Joining a call on Zoom/Teams/whatever already takes a few seconds, so there’s no excuse for this “optimization”.
  - kitsunesoba 5y ago
    I totally agree, but nevertheless this is a behavior I’ve seen in several audio/video call apps.
- diebeforei485 5y ago
  macOS Monterey is going to make it more obvious in UI when an app is using the microphone. Hopefully sunlight is a good disinfectant and acts as a forcing function for apps to fix up their behavior.
saagarjha 5y ago
> I also recently discovered that something like 12% of CPU on my 2020 macbook air is used whenever I'm in a room with anything greater than perfect silence, by 'coreaudiod', because it apparently is constantly listening to the microphone built in near the keyboard and spending cpu cycles trying to filter out background noise. Have you tried sampling the process to ensure that it is actually doing this? If it is, it's likely that Signal is leaving open a recording session and it shouldn't, and given that the app is open source, it should be fairly easy to find where it is doing this. I am sure they would be very interested in such a report, considering the privacy implications of leaving the audio system up when it shouldn't be.
interestica 5y ago
The 2020 M1 version or previous Intel iteration (or perhaps there's no difference)?
- walrus01 5y ago
  Intel i7
- cassianoleal 5y ago
  I have Signal open on my M1 MacBook Air, and coreaudiod is using 0.0 CPU. The app itself uses anything between 1.5 and 8% CPU just for being open though, mostly the renderer process. That's true even if the window is minimised or hidden. With Slack open, coreaudiod also sits most of the time at 0%. Animations, scrolling and generally just using the app can make it go up to 30-50% for a few seconds, between the GPU and the renderer processes.
MontyCarloHall 5y ago
> Imagine the cumulative kilowatt-hours wasted globally by all the CPU cycles spent by slack just to exist as basically a glorified IRC app. Conversely, imagine the global kWh saved by some micro-optimization to a key system call like malloc. Perhaps the biggest positive impact a single developer can have on our climate is to improve the efficiency of frequently used pieces of code. Even tiny optimizations would add up.
- saagarjha 5y ago
  They are highly optimized for exactly this reason.
  - IshKebab 5y ago
    The Mac allocator is terrible. Presumably there's some backwards compatibility reason but it's much much slower than Glibc, tcmalloc or jemalloc. I'm not sure about Windows.
- reificator 5y ago
  The more efficient computers are, the more people will use and rely on computers.
  - mrpopo 5y ago
    The mote efficient computers are, the less developers will spend time optimizing their apps.
newscracker 5y ago
> … 'coreaudiod', because it apparently is constantly listening to the microphone built in near the keyboard and spending cpu cycles trying to filter out background noise. Apparently running the signal desktop app in the background is enough to keep coreaudiod constantly wasting battery. Because signal is open and has been granted permissions for microphone and speakers, even if no call session is open? There’s an app called Micro Snitch [1] that will alert the user when any application activates the microphone or the webcam and tell the user which application is doing it (including Apple’s apps like FaceTime). You could try it to confirm that it is indeed Signal that’s activating the microphone at all times and file a bug report with Signal. Listening in the background is a very serious issue because we don’t expect Signal to do that. Edit: FWIW, I just remembered that I have Signal and Micro Snitch on an old MBP (running the latest macOS). I have never seen alerts for microphone activation when Signal is running (I don’t use it for calls from the computer). Nevertheless, if the coreaudiod issue is with an app using the mic, Micro Snitch may help. [1]: https://obdev.at/products/microsnitch/index.html https://obdev.at/products/microsnitch/index.html
- underdeserver 5y ago
  It's ironic. After all the time people spend accusing Facebook and others of opening your mic, it's Signal that's actually doing it
  - hansel_der 5y ago
    then again, this does not proof that others aren't doing it as well
- diebeforei485 5y ago
  macOS Monterey (likely release this month or next) has this built-in.
marderfarker2 5y ago
Thought only my cheapo Dell does this. DSP should’ve been offloaded to dedicated audio hardware. Doing it in software is just lazy.
- sgtnoodle 5y ago
  I have a lot of nostalgia for PCI sound cards from the late 90's and early 2000's. That being said, I am happy that PC audio has been simplified to just minimally buffered DACs and ADCs, or a digital interconnect. Things actually just work without having to futz with ugly skinned proprietary software.
grahamplace 5y ago
> I also recently discovered that something like 12% of CPU on my 2020 macbook air is used whenever I'm in a room with anything greater than perfect silence, by 'coreaudiod', because it apparently is constantly listening to the microphone built in near the keyboard and spending cpu cycles trying to filter out background noise. Apparently running the signal desktop app in the background is enough to keep coreaudiod constantly wasting battery. Are you sure it's the Signal desktop app? My initial hunch was while reading was that maybe it's your machine constantly listening for a "Hey Siri". There are some reports of the same issue (and a possible solution) here: https://apple.stackexchange.com/questions/24913/why-is-the-coreaudiod-daemon-using-5-or-more-cpu https://apple.stackexchange.com/questions/24913/why-is-the-c... Though none of them mention Signal in particular.
- quenix 5y ago
  I believe Hey Siri functionality is handled by lower level audio chips, not in user land. At least that’s how it’s done on the iPhone
  - diebeforei485 5y ago
    "Hey Siri" on macOS is done in hardware, using the onboard T2 chip (not the CPU). Or, when using newer AirPods with H1 chip, the "Hey Siri" listening is done on the AirPods.
sgtnoodle 5y ago
I needed some excessive CPU load to stress test a program's tolerance to scheduling contention, so I reloaded my chrome slack tab every 15 seconds. It worked surprisingly well...
deleted 5y ago
[deleted]
pthatcherg 5y ago
Hi, I work at Signal on calling. Opening the mic while not in a call would be a serious bug, so I looked into it. I ran Micro Snitch and verified that it only sees the mic as active when you are in a call with someone (if you're in a group call and alone, keeps the mic off; if you're calling someone and they haven't answered yet, it keeps the mic off). So I don't think it's an issue with calling. However, if I hit the "record audio message" button and then hit cancel, I can get it to stay open until I close the app and restart it. I will report this bug to my coworkers at Signal that work in that area of the code. Could you try and see if this problem is caused by the voice recording feature? For example, if you quit Signal and start back up, does the bug go away? If you start a voice recording and cancel it, does it come back? Update: you can track the progress of the bug at https://signalmessenger.atlassian.net/browse/DESKTOP-2406 https://signalmessenger.atlassian.net/browse/DESKTOP-2406 And if you have new information, please put it there.

lostlogin 5y ago

> If you really want to see slack waste CPU and battery, leave a channel open that somebody has pasted a high FPS animated GIF into This is basically an attack especially if you post a couple of them. My god.

fotta 5y ago
I basically avoid large channels at work because it just absolutely bogs down my machine.
- waspight 5y ago
  Just turning off animations in settings would help I guess
  - throwaway09223 5y ago
    connecting to slack from a third party application is even better.
art0rz 5y ago
It is really surprising how bad/slow Slack is compared to Discord
- hansel_der 5y ago
  i assumed as much given one is made for gamers and the other for corporates.

kitsunesoba 5y ago

The coreaudiod issue might have to do with apps that use the mic "priming" it by keeping it active even when there's no call. Some chat apps do this to avoid the 1-2s delay associated with turning on the mic, so audio starts streaming as soon as the call starts.

Kwpolska 5y ago
Keeping the mic active when you’re in a call but have the mic muted is acceptable and understandable. At any other time, it would make me think the app is recording everything and shipping the recordings to the friendly neighborhood TLA agent. Joining a call on Zoom/Teams/whatever already takes a few seconds, so there’s no excuse for this “optimization”.
- kitsunesoba 5y ago
  I totally agree, but nevertheless this is a behavior I’ve seen in several audio/video call apps.
diebeforei485 5y ago
macOS Monterey is going to make it more obvious in UI when an app is using the microphone. Hopefully sunlight is a good disinfectant and acts as a forcing function for apps to fix up their behavior.

saagarjha 5y ago

> I also recently discovered that something like 12% of CPU on my 2020 macbook air is used whenever I'm in a room with anything greater than perfect silence, by 'coreaudiod', because it apparently is constantly listening to the microphone built in near the keyboard and spending cpu cycles trying to filter out background noise. Have you tried sampling the process to ensure that it is actually doing this? If it is, it's likely that Signal is leaving open a recording session and it shouldn't, and given that the app is open source, it should be fairly easy to find where it is doing this. I am sure they would be very interested in such a report, considering the privacy implications of leaving the audio system up when it shouldn't be.

interestica 5y ago

The 2020 M1 version or previous Intel iteration (or perhaps there's no difference)?

walrus01 5y ago
Intel i7
cassianoleal 5y ago
I have Signal open on my M1 MacBook Air, and coreaudiod is using 0.0 CPU. The app itself uses anything between 1.5 and 8% CPU just for being open though, mostly the renderer process. That's true even if the window is minimised or hidden. With Slack open, coreaudiod also sits most of the time at 0%. Animations, scrolling and generally just using the app can make it go up to 30-50% for a few seconds, between the GPU and the renderer processes.

MontyCarloHall 5y ago

> Imagine the cumulative kilowatt-hours wasted globally by all the CPU cycles spent by slack just to exist as basically a glorified IRC app. Conversely, imagine the global kWh saved by some micro-optimization to a key system call like malloc. Perhaps the biggest positive impact a single developer can have on our climate is to improve the efficiency of frequently used pieces of code. Even tiny optimizations would add up.

saagarjha 5y ago
They are highly optimized for exactly this reason.
- IshKebab 5y ago
  The Mac allocator is terrible. Presumably there's some backwards compatibility reason but it's much much slower than Glibc, tcmalloc or jemalloc. I'm not sure about Windows.
reificator 5y ago
The more efficient computers are, the more people will use and rely on computers.
- mrpopo 5y ago
  The mote efficient computers are, the less developers will spend time optimizing their apps.

newscracker 5y ago

> … 'coreaudiod', because it apparently is constantly listening to the microphone built in near the keyboard and spending cpu cycles trying to filter out background noise. Apparently running the signal desktop app in the background is enough to keep coreaudiod constantly wasting battery. Because signal is open and has been granted permissions for microphone and speakers, even if no call session is open? There’s an app called Micro Snitch [1] that will alert the user when any application activates the microphone or the webcam and tell the user which application is doing it (including Apple’s apps like FaceTime). You could try it to confirm that it is indeed Signal that’s activating the microphone at all times and file a bug report with Signal. Listening in the background is a very serious issue because we don’t expect Signal to do that. Edit: FWIW, I just remembered that I have Signal and Micro Snitch on an old MBP (running the latest macOS). I have never seen alerts for microphone activation when Signal is running (I don’t use it for calls from the computer). Nevertheless, if the coreaudiod issue is with an app using the mic, Micro Snitch may help. [1]: https://obdev.at/products/microsnitch/index.html https://obdev.at/products/microsnitch/index.html

underdeserver 5y ago
It's ironic. After all the time people spend accusing Facebook and others of opening your mic, it's Signal that's actually doing it
- hansel_der 5y ago
  then again, this does not proof that others aren't doing it as well
diebeforei485 5y ago
macOS Monterey (likely release this month or next) has this built-in.

marderfarker2 5y ago

Thought only my cheapo Dell does this. DSP should’ve been offloaded to dedicated audio hardware. Doing it in software is just lazy.

sgtnoodle 5y ago
I have a lot of nostalgia for PCI sound cards from the late 90's and early 2000's. That being said, I am happy that PC audio has been simplified to just minimally buffered DACs and ADCs, or a digital interconnect. Things actually just work without having to futz with ugly skinned proprietary software.

grahamplace 5y ago

> I also recently discovered that something like 12% of CPU on my 2020 macbook air is used whenever I'm in a room with anything greater than perfect silence, by 'coreaudiod', because it apparently is constantly listening to the microphone built in near the keyboard and spending cpu cycles trying to filter out background noise. Apparently running the signal desktop app in the background is enough to keep coreaudiod constantly wasting battery. Are you sure it's the Signal desktop app? My initial hunch was while reading was that maybe it's your machine constantly listening for a "Hey Siri". There are some reports of the same issue (and a possible solution) here: https://apple.stackexchange.com/questions/24913/why-is-the-coreaudiod-daemon-using-5-or-more-cpu https://apple.stackexchange.com/questions/24913/why-is-the-c... Though none of them mention Signal in particular.

quenix 5y ago
I believe Hey Siri functionality is handled by lower level audio chips, not in user land. At least that’s how it’s done on the iPhone
- diebeforei485 5y ago
  "Hey Siri" on macOS is done in hardware, using the onboard T2 chip (not the CPU). Or, when using newer AirPods with H1 chip, the "Hey Siri" listening is done on the AirPods.

sgtnoodle 5y ago

I needed some excessive CPU load to stress test a program's tolerance to scheduling contention, so I reloaded my chrome slack tab every 15 seconds. It worked surprisingly well...

deleted 5y ago

[deleted]

pthatcherg 5y ago

Hi, I work at Signal on calling. Opening the mic while not in a call would be a serious bug, so I looked into it. I ran Micro Snitch and verified that it only sees the mic as active when you are in a call with someone (if you're in a group call and alone, keeps the mic off; if you're calling someone and they haven't answered yet, it keeps the mic off). So I don't think it's an issue with calling. However, if I hit the "record audio message" button and then hit cancel, I can get it to stay open until I close the app and restart it. I will report this bug to my coworkers at Signal that work in that area of the code. Could you try and see if this problem is caused by the voice recording feature? For example, if you quit Signal and start back up, does the bug go away? If you start a voice recording and cancel it, does it come back? Update: you can track the progress of the bug at https://signalmessenger.atlassian.net/browse/DESKTOP-2406 https://signalmessenger.atlassian.net/browse/DESKTOP-2406 And if you have new information, please put it there.