Samsung Introduces "LAB" Linux Frequency Governor
Phoronix: Samsung Introduces "LAB" Linux Frequency Governor
Samsung developers last week provided patches for a new cpufreq governor dubbed "LAB", or the "Legacy Application Boost", for the Linux kernel...
That won't work!
That won't work out as the Samsung engineers expected.
It is a common misconception the powersave governor actually runs more efficient than ondemand.
The opposite is true: Running at a lower clockrate increases the time until the CPU can jump back into Idle state, which in turn increases the load-time and energy consumption.
So, when the Samsung engineers want to lower the frequency in case mutliple cores are under heavy load, the frequency would effectively be lowered when the system is under heavy, parallelized load
, effectively increasing the load time.
This is not effective.
It reduces the heat output tremendously.
Have you ever tried to run Linux on a notebook using a full AMD stack (AMD processor + AMD graphics cards + AMD northbridge) without forcing the powersave govenor to be active at all times? You can literally soften a pencil eraser enough to remould it after putting it behind the notebook's vents.
I speak from personal experience.
Last edited by Sonadow; 04-10-2013 at 01:05 AM.
My observations as well. Anything other than the powersave governor makes my HTPC fry itself once it tries to do more or less anything that is remotely demanding (due to fairly low air flow capability). With powersave, it never reaches dangerous temperatures. This is also with an AMD (Phenom II) processor.
Originally Posted by Sonadow
Less heat, but more energy consumption
The computer runs with less Watts over a longer period of time. In effect, it runs cooler, but computation needs more energy overall.
Originally Posted by GreatEmerald
Just tell me if you want me to give you an example.
Thankfully, an HTPC never really needs to do anything extraordinarily complex with computations.
Originally Posted by frign
We're aware that it uses more frign, but for some bizarre reason linux seems to be worse at thermal management than windows (I dont know how thats possible... im just speaking from experience.)
Originally Posted by frign
For example. This very laptop (Dell XPS 13z) running Arch linux, if I place it on my lap in such a way that my leg blocks the vent the laptop will gradually rise in temperature until it hits 95C and then BIOS kills the power to the entire laptop to prevent damage.
The same laptop running Windows 7 doing the same thing, also with my leg blocking the vent, will hit 85C and stay there, never shutting down.
^While anecdotal evidence, this isnt a "This happened once, so im telling the story." I had Arch Linux on this laptop for about 8 months or so and would accidentally overheat it at least once a week. I've had Win7 on this thing for about a month now and havent accidentally overheated it even once.
If I ever put arch linux back on this laptop I very well may stick to the powersave governor just to make sure I dont accidentally damage the internals from thermal output