Linux 4.6 Will Fix A Bug Where Some Laptops Are Always Throttled With Bad Performance

[phoronix]

Phoronix: Linux 4.6 Will Fix A Bug Where Some Laptops Are Always Throttled With Bad Performance

The thermal updates were submitted today for the Linux 4.6 kernel merge window and there's a very important fix for at least some newer Lenovo laptops. The fix should end up getting backported to current stable series, but if you have a Lenovo laptop and have been seeing slower performance on recent Linux kernel versions, you'll want to upgrade...

http://www.phoronix.com/scan.php?page=news_item&px=Linux-4.6-Thermal-Updates

[edmon]

:P soorry

[drohm]

I'm curious what the valid trip points are...

[SystemCrasher]

There is also "reverse" problem. Some hardware reports bizarre trip points exceeding 100C, which is insane. This has been seen on both x86 and ARM hardware, btw. Sorry, but operating IC at >=100C is doomed to be unstable, extremely hot and I wouldn't count on anyhow long life of IC under these conditions. This means: thermal protection virtually fails to work for some ICs. I think kernel/drivers should override obviously bizarre trip points.

[duby229]

There is also "reverse" problem. Some hardware reports bizarre trip points exceeding 100C, which is insane. This has been seen on both x86 and ARM hardware, btw. Sorry, but operating IC at >=100C is doomed to be unstable, extremely hot and I wouldn't count on anyhow long life of IC under these conditions. This means: thermal protection is virtually fails to work for some ICs.

Yep and that is an extremely common problem. At least on laptops though the primary cause is a dust mat built up on the heatsink fins. A can of air can blast it into the guts of the machine or get tangled up in the heatsink fan, so the best idea is take the laptop apart and properly clean it. If you do see an Intel laptop running at 100+, that is almost surely the cause.

[Veerappan]

Hmm, given that I've got a Thinkpad T440p at work, I'll have to see when this gets merged in and built into an Ubuntu kernel I can download (cause I'm too lazy right now to do it myself).

[Xelix]

Hmm, given that I've got a Thinkpad T440p at work, I'll have to see when this gets merged in and built into an Ubuntu kernel I can download (cause I'm too lazy right now to do it myself).

Where did you see that this patch would benefit the T440p? (I'm asking because I have the same laptop)

[Dea1993]

i hope that will be fixed also the bug of the keyboard of hp pavilion 15 ab062nl (and other hp pavilion 15 models)

[SystemCrasher]

Yep and that is an extremely common problem. At least on laptops though the primary cause is a dust mat built up on the heatsink fins. A can of air can blast it into the guts of the machine or get tangled up in the heatsink fan, so the best idea is take the laptop apart and properly clean it. If you do see an Intel laptop running at 100+, that is almost surely the cause.

Well, I've seen laptops reporting their critical trip points of 105C or so, that's how vendors are filling ACPI tables. Which is waaaaaaay to much. Even if CPU can withstand it (some CPUs are rated to 90C only!), it warrants extremely hot device, close to plastic parts melting point. I've also seem some ARMs reporting similar trip points. Needless to say, board goes unstable way before 105C is reached by CPU and throttle activates, making it nearly useless. Some vendors clearly overrate their abilities or do not give a fuck about filling tables/defaults properly.

The point wasn't about cleaning laptop or something. The point is that thermal protection isn't what I would call protective in many cases. It supposed to kick in in such cases, keeping system operations stable and saving IC from fatal overheating. Yet it hard to admit thermal protection always achieves these goals. Half of time it just missing the point, targeting really bizarre trip points.

[Zan Lynx]

Well, I've seen laptops reporting their critical trip points of 105C or so, that's how vendors are filling ACPI tables. Which is waaaaaaay to much. Even if CPU can withstand it (some CPUs are rated to 90C only!), it warrants extremely hot device, close to plastic parts melting point. I've also seem some ARMs reporting similar trip points. Needless to say, board goes unstable way before 105C is reached by CPU and throttle activates, making it nearly useless. Some vendors clearly overrate their abilities or do not give a fuck about filling tables/defaults properly.

To be fair, the critical trip point is never supposed to be reached. When the system hits that critical point it is supposed to shut down. Immediately. With the bare minimum of doing a filesystem sync.

Far before that point at about 80°C, the CPU is supposed to start clock throttling. That 105° mark indicates something seriously wrong such as a complete cooling failure.