Mr. Steve, on 12 February 2012 - 12:22 AM, said:
Even more complicated request, can we get HotplugX but with the scaling that is used in Interactive; so I guess you could call it InteractiveHotplugX...
You can tweak the sysfs values of hotplug to obtain similar results to interactive but then you lose some of the battery savings of hotplug scaling (which is just like ondemand). It will still disable CPU1 as set though. Imoseyon listed the tunables in this post:
imoseyon, on 06 February 2012 - 07:56 PM, said:
Android38 asked me about tunable options for hotplug governor now that it's more or less stable:
(This is for advanced users who are comfortable messing with sysfs)
All of the above are tunable - some are fairly obvious based on file names, some are not. :)
io_is_busy is one I would leave at 0, as that from what I can understand, changing setting that (to 1) will allow the OS to shut off CPU1 when in the middle of a disk read or write operation and that seems like it could have the potential for data loss.
up_threshold is the percent of max load at the current frequency step before it ramps to maximum speed.
down_threshold is the percent of load that the system has to drop down to before it will scale down a step. (From what I understand this is a range that is determined by the down_differential to allow for minor fluctuations. For example if you have down_differential set at 10 and down_threshold set to 30 and your load is jumping between 28 and 32 it would still scale down as you wouldn't want it to keep jumping back up.)
sampling_rate is how frequently in µs (1x10`^-6 or .000001 seconds) the governor will check for CPU load. The faster it is (lower number) the more responsive it will be at the sacrifice of battery life.
hotplug_out_sampling_periods is how many samples of the sampling_rate show low enough load to disable CPU1.
hotplug_in_sampling periods is the same as above but how many periods before it turns CPU1 back on.
ignore_nice_load would from what I understand ignore all process priority and give all processes equal priority. I wouldn't recommend changing this, but you can play with it, but you may get undesired results.
If you don't tweak these with a script, you can tweak them on the fly with terminal or even a text editor. If something causes issues just reboot and the settings will be reverted. With these settings you can really tune hotplug to your liking as far as performance vs. battery.
So... If hotplugX could be made it could be tuned to scale very close to Interactive. I know it would not quite be InteractiveHotplugX, but it could operate similar (assuming if imo makes it and he makes it tunable with sysfs). Also the values can be set in init scripts so they can set at boot if you find a good combl.
I know that is more than you asked, but there are so many things you can do that most people don't know exist since they can be not only hidden but a bit technical.
imoseyon, if you see anything I got wrong, feel free to correct me.
Edited by abqnm, 12 February 2012 - 01:05 AM.