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Try charging on the right and not on the left

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Re: Try charging on the right and not on the left

#11

Post by neogodless »

mkl wrote: post #4
causi wrote: post #2

high CPU usage by kernel_task is caused by high Thunderbolt Left Proximity temperature, which is caused by charging and having normal peripherals plugged in at the same time. Did anyone ever figure out why exactly the temperature sensor was making kernel_task go crazy?

The comment by jksoegaard may explain it: "the purpose of the thread is to force idleness". I guess it uses up all the CPU without actually making the CPU do anything, so other processes can't use the CPU and produce more heat than it can handle.

Wow! This brings back memories. I don't remember which generation of CPUs this was.. maybe Pentium III or AthlonXP. But there was an issue in Windows where the chip would overheat when idle.

There was an app called Rain that you could download and it would just keep the idle process from running away and causing heat. I may need to research this on my lunch break and report back.

EDIT: Here's a related thread: https://arstechnica.com/civis/viewtopic.php?f=8&t=1060257

Re: Try charging on the right and not on the left

#12

Post by whywhywhywhy »

kuu wrote: post #10

How does something like this happen without QA knowing and Apple fixing it? I mean, it's happening cause charging it, that's something all users will do :S Sounds a lot like the antennagate

They spotted it and made the trade off that it wasn’t worth fixing

Re: Try charging on the right and not on the left

#13

Post by wongarsu »

shrx wrote: post #6
mkl wrote: post #4

Earlier quoted context omitted.

The comment by jksoegaard may explain it: "the purpose of the thread is to force idleness". I guess it uses up all the CPU without actually making the CPU do anything, so other processes can't use the CPU and produce more heat than it can handle.

Documented here: https://support.apple.com/en-us/HT207359

> One of the functions of kernel_task is to help manage CPU temperature by making the CPU less available to processes that are using it intensely. In other words, kernel_task responds to conditions that cause your CPU to become too hot

If it's about CPU temperature, why does Apple schedule a task instead of just downclocking the CPU, like everyone else? This question predates the release of M1 Macbooks, and everyone else does thermal management of Intel Core processors via clock speed, not artificial idle load.

Re: Try charging on the right and not on the left

#14

Post by danlugo92 »

WA wrote: post #8
xgbi wrote: post #3

This doesn't make sense, and I'm a bit worried: I "cheaped" out and have a "left side only USB-C" MBPro from 2019. Should I understand that having any kind of load on the measly 2 ports I have on my 1600€ computer will lead to abysmal performance? Like, attaching a USB hub to add basic necessity like HDMI or USB A?

Attach an LG Ultrafine 5K and you can fry an egg on your €3,300 laptop and use the white noise from the fan to sleep well.

Attach the same monitor to both an M1 and an Intel Laptop, you can fry chicken on the latter.

Re: Try charging on the right and not on the left

#15

Post by majou »

wongarsu wrote: post #13
shrx wrote: post #6

Earlier quoted context omitted.

Documented here: https://support.apple.com/en-us/HT207359

> One of the functions of kernel_task is to help manage CPU temperature by making the CPU less available to processes that are using it intensely. In other words, kernel_task responds to conditions that cause your CPU to become too hot If it's about CPU temperature, why does Apple schedule a task instead of just downclocking the CPU, like everyone else? This question predates the release of M1 Macbooks, and everyone…

It would reduce latency of tasks to do it this way.

Re: Try charging on the right and not on the left

#16

Post by gambiting »

danlugo92 wrote: post #14
WA wrote: post #8

Earlier quoted context omitted.

Attach an LG Ultrafine 5K and you can fry an egg on your €3,300 laptop and use the white noise from the fan to sleep well.

Attach the same monitor to both an M1 and an Intel Laptop, you can fry chicken on the latter.

Can you? My i5-10300H equipped laptop drives two external monitors daily and the fans don't even start in normal use. Maybe specify which laptop?

The M1 can't even support two monitors plugged in directly, which is a joke for a machine this expensive.

Re: Try charging on the right and not on the left

#17

Post by nkozyra »

whywhywhywhy wrote: post #12
kuu wrote: post #10

How does something like this happen without QA knowing and Apple fixing it? I mean, it's happening cause charging it, that's something all users will do :S Sounds a lot like the antennagate

They spotted it and made the trade off that it wasn’t worth fixing

Or alternately, spotted it and decided to make their own chip.

Re: Try charging on the right and not on the left

#18

Post by hunter2_ »

nikanj wrote: post #9
xgbi wrote: post #3

This doesn't make sense, and I'm a bit worried: I "cheaped" out and have a "left side only USB-C" MBPro from 2019. Should I understand that having any kind of load on the measly 2 ports I have on my 1600€ computer will lead to abysmal performance? Like, attaching a USB hub to add basic necessity like HDMI or USB A?

Yes. But the computer is very, very, very thin. Which sells more computers than actual performance under load. Benchmarks show the MB having decent performance, as they start cold and don’t have external devices attached either. Thermal throttling only shows up once you’ve already bought

Reminiscent of the Volkswagen dieselgate situation where emissions are fine during the EPA test drive but horrible otherwise. This sort of thing will probably haunt us forever, in various forms.
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