** WORKAROUND**: shut down the thermald process completely. If your computer has an actual physical cooling fan and it's fully functional, you don't need thermald at all.
I have Ubuntu 15.10 up to date with automatic updates and I never touched thermald configuration.
This is on a laptop, which has an actual physical cooling fan (like most laptops).
EXPECTED BEHAVIOR:
as the CPU temperature increases, the fan should spin faster to keep the temperature from getting too high. ONLY IF, even with the fan at its full capacity, or approaching it, the temperature keeps growing, THEN that's when things like intel powerclamp and things like that should trigger, throttling the CPU, so that it doesn't burn (or shut down abruptly). Also, these kinds of CPU throttling should come in gradually as needed. That is, if you inject idle processes, you should inject just the minimum amount that is needed. For example, if the fan at its maximum speed is *almost* enough to keep the temperature below the threshold, but not *quite* enough, injecting just a small amount of idle time into the CPU should be enough to do that extra bit of cooling that is needed. You would barely notice it. It would not slow your system down a lot, unless the heating is *way* higher than the fan alone can fight.
On a fully functional system (where the fan is enough to prevent the CPU from overheating and/or excessive CPU consumption does not occur in a huge degree for a long time), you shouldn't note any difference by shutting down thermald completely. Only on a system where the fan is not fully functional and/or hugely excessive CPU usage goes on for too long (actually, if the latter alone is enough to make it happen, it means that the fan is underdimensioned) would you note the difference between having thermald (powerclamp and other CPU throttling mechanisms would kick in and prevent the temperature from becoming critical) and not having it (temperature would eventually go critical and something bad would happen, such as a sudden shutdown)
OBSERVED BEHAVIOR
When CPU temperature becomes high due to relatively high (not huge) CPU consumption, intel_powerclamp starts to kick in injecting idle processes and crippling the whole system. The observable result is that the system becomes unresponsive and unusable, yet the physical fan is sponning at roughly HALF of its maximum speed. So, you have a fast quad core machine, with a cooling fan that is perfectly capable of keeping the temperature down while using all the computing power that you require, BUT since powerclamp and things like that kick in too soon, you are limited to use a tiny fraction of the power your machine is capable of.
To put it another way: you can't watch a f***ing youtube video in full screen because the whole system will become unresponsive.
Even after removing and blacklisting the intel_powerclamp and intel_rapl kernel modules, the apparent behavior was practically the same, except that I wouldn't observe the "kidle_inject" processes by running "top". I guess there are other CPU-throttling mechanisms besides powerclamp and rapl.
So now I have SHUT DOWN THERMALD completely, and my system behaves NORMALLY. The fan, of course, reaches higher speeds. Not even _much_ higher, which means that in needed just a little bit more speed to keep up with the heating. Powerclamp and other cpu throttling mechanisms were kicking in WAY too soon.
It took me quite a long time to figure out that this was the problem. I just assumed that some bug was causing excessive CPU consumption for trivial stuff such as playing video (which is actually true but is not the whole story) and that the CPU consumption actually was causing too much heat for the fan to dissipate, making it necessary for powerclamp to kick in. Also, I thought my fan was probably filled with dust and uncapable of doing its job efficiently (which is also true but is not the whole story).
Until I realised that when I was observing unresponsiveness, the fan was not even close to its maximum speed.
CONCLUSION: either thermald does a ridiculously bad job, or its default configuration is ridiculously bad.
NOTE: this issue is **CRITICAL**: this cripples the whole system making it unresponsive when doing moderately heavy work (which the system would otherwise be perfectly capable of handling without overheating).
Most non-geek users don't even know what thermald is and will never find out that they can work around the problem by shutting it down, let alone fix its configuration. So, for most users, this "renders the system temporarily or permanently unusable", which is one of the criteria for critical importance.
ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: thermald 1.4.3-5ubuntu2
ProcVersionSignature: Ubuntu 4.2.0-41.48-generic 4.2.8-ckt11
Uname: Linux 4.2.0-41-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CurrentDesktop: Unity
Date: Sun Jul 10 14:03:56 2016
InstallationDate: Installed on 2013-10-11 (1002 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
SourcePackage: thermald
UpgradeStatus: Upgraded to wily on 2016-01-18 (174 days ago)
** WORKAROUND**: shut down the thermald process completely. If your computer has an actual physical cooling fan and it's fully functional, you don't need thermald at all.
I have Ubuntu 15.10 up to date with automatic updates and I never touched thermald configuration.
This is on a laptop, which has an actual physical cooling fan (like most laptops).
EXPECTED BEHAVIOR:
as the CPU temperature increases, the fan should spin faster to keep the temperature from getting too high. ONLY IF, even with the fan at its full capacity, or approaching it, the temperature keeps growing, THEN that's when things like intel powerclamp and things like that should trigger, throttling the CPU, so that it doesn't burn (or shut down abruptly). Also, these kinds of CPU throttling should come in gradually as needed. That is, if you inject idle processes, you should inject just the minimum amount that is needed. For example, if the fan at its maximum speed is *almost* enough to keep the temperature below the threshold, but not *quite* enough, injecting just a small amount of idle time into the CPU should be enough to do that extra bit of cooling that is needed. You would barely notice it. It would not slow your system down a lot, unless the heating is *way* higher than the fan alone can fight.
On a fully functional system (where the fan is enough to prevent the CPU from overheating and/or excessive CPU consumption does not occur in a huge degree for a long time), you shouldn't note any difference by shutting down thermald completely. Only on a system where the fan is not fully functional and/or hugely excessive CPU usage goes on for too long (actually, if the latter alone is enough to make it happen, it means that the fan is underdimensioned) would you note the difference between having thermald (powerclamp and other CPU throttling mechanisms would kick in and prevent the temperature from becoming critical) and not having it (temperature would eventually go critical and something bad would happen, such as a sudden shutdown)
OBSERVED BEHAVIOR
When CPU temperature becomes high due to relatively high (not huge) CPU consumption, intel_powerclamp starts to kick in injecting idle processes and crippling the whole system. The observable result is that the system becomes unresponsive and unusable, yet the physical fan is sponning at roughly HALF of its maximum speed. So, you have a fast quad core machine, with a cooling fan that is perfectly capable of keeping the temperature down while using all the computing power that you require, BUT since powerclamp and things like that kick in too soon, you are limited to use a tiny fraction of the power your machine is capable of.
To put it another way: you can't watch a f***ing youtube video in full screen because the whole system will become unresponsive.
Even after removing and blacklisting the intel_powerclamp and intel_rapl kernel modules, the apparent behavior was practically the same, except that I wouldn't observe the "kidle_inject" processes by running "top". I guess there are other CPU-throttling mechanisms besides powerclamp and rapl.
So now I have SHUT DOWN THERMALD completely, and my system behaves NORMALLY. The fan, of course, reaches higher speeds. Not even _much_ higher, which means that in needed just a little bit more speed to keep up with the heating. Powerclamp and other cpu throttling mechanisms were kicking in WAY too soon.
It took me quite a long time to figure out that this was the problem. I just assumed that some bug was causing excessive CPU consumption for trivial stuff such as playing video (which is actually true but is not the whole story) and that the CPU consumption actually was causing too much heat for the fan to dissipate, making it necessary for powerclamp to kick in. Also, I thought my fan was probably filled with dust and uncapable of doing its job efficiently (which is also true but is not the whole story).
Until I realised that when I was observing unresponsiveness, the fan was not even close to its maximum speed.
CONCLUSION: either thermald does a ridiculously bad job, or its default configuration is ridiculously bad.
NOTE: this issue is **CRITICAL**: this cripples the whole system making it unresponsive when doing moderately heavy work (which the system would otherwise be perfectly capable of handling without overheating).
Most non-geek users don't even know what thermald is and will never find out that they can work around the problem by shutting it down, let alone fix its configuration. So, for most users, this "renders the system temporarily or permanently unusable", which is one of the criteria for critical importance.
ProblemType: Bug ature: Ubuntu 4.2.0-41.48-generic 4.2.8-ckt11 dules: nvidia
DistroRelease: Ubuntu 15.10
Package: thermald 1.4.3-5ubuntu2
ProcVersionSign
Uname: Linux 4.2.0-41-generic x86_64
NonfreeKernelMo
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CurrentDesktop: Unity
Date: Sun Jul 10 14:03:56 2016
InstallationDate: Installed on 2013-10-11 (1002 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
SourcePackage: thermald
UpgradeStatus: Upgraded to wily on 2016-01-18 (174 days ago)