[Galaxy Tab 7.7 Android Development] UpInTheAir:
FAQ & HELP

FAQ & HELP

MY RECOMMENDATIONS

* Governor = pegasusq - lulzactiveq - ZZMoove

* IMO = Performance → → Battery

1. on-demand

2. pegasusq

3. lulzactiveq

4. ZZMoove​

* Scheduler = SIO

* CPU freq = 200-1400/1600 MHz

* CPU vdd levels = SkyHigh "defaults"

* Enable zRAM

* CPU Control app = Trickster Mod app

Don't forget to use only one Control app at a time. They will conflict !

ISSUES?

1 Remove any kernel related init.d tweaks

2 Wipe your CPU control app(s) data (menu > settings > applications > "your control app(s)" > clear data/cache)

3 Use only ONE CPU control app !

4 Open SuperSU app > settings > full unroot

5 Boot into recovery and wipe cache & dalvik cache

6 Flash SkyHigh Kernel

7 Reboot

BASIC TRICKSTER MOD APP TUTORIAL

** Open app and ensure SU permission is granted **

1. Make your changes

2. Apply (tap the "✔")

3. Enable (I use notification as well)

4. Reboot, you can see the notification after start-up

zRAM

Info here : (INFO)What is zram and how does it work???

PREVENT/REDUCE SCREEN-OFF FLICKER FOR CRT-OFF ANIMATION ENABLED ROMs

* set fbearlysuspend msleep between 100 and 500 ms

* Set to 0 if you haven't any CRT-off animation mod

DYNAMIC READ-AHEAD

DYNAMIC FSYNC CONTROL

DYNAMIC MANAGEMENT OF DIRTY PAGE WRITEBACKS

* [Christopher83]

ANDROID LOGGER SYSFS INTERFACE

* Switching done via /sys/kernel/logger_mode interface

* Default is 0 (off)

WHAT IS A CUSTOM KERNEL

* Is 'usually' modified and complied from source.

* My very first successfully compiled kernel just included the "SkyHigh" name. I suppose you could call that a modified "stock" kernel. On the other hand, you could also argue that any firmware modified from either official or built from sources could be called "custom". :)

HAVE THE STOCK KERNELS ATTACHED BEEN MODIFIED

* If you are referring to the stock MD3 kernels in Post #2, NO

* I just extracted the zImage from official firmware and repackaged for flashing via custom recovery or Odin. There are no changes made to the zImage. I have no plans to modify these.

ENTROPY

* MAX pool sixe 4096

* It's not instant, just use your device and it will grow.

* No need for entropy generator apps that consume battery (use extra CPU cycles)

WHAT ARE GOVERNORS / SCHEDULERS ETC

* Excellent source of info by droidphile :

[REF][TWEAKS] Kernel Governors, Modules, I/O Schedulers, CPU Tweaks, AIO App Configs

CUSTOM BOOT ANIMATION SUPPORT

1. copy bootanimation.zip to /system/media/ folder (mount folder r/w to paste)

2. ensure set permissions rw-rw-rw-

3. reboot

NOTE :

* For any further help or instructions for bootanimation, please open your own forum Q&A thread or post in a relevant bootanimation thread. There are many already built and can be found by searching.

* The size we need for our tab is 800x1280 or 1280x800 (depending on portrait or landscape)

CUSTOM BOOT SOUND SUPPORT

* Place custom boot sound PowerOn.ogg in /system/media

* To mute, create an empty file named mute in /system/media

* To unmute, create an empty file named unmute in /system/media

* To restore original boot sound, create an empty file named ori_sound in /system/media

* Reboot device after each process

NOTE :

* when creating a custom boot sound, make sure you use a capital "P" and "O" in PowerOn.ogg

* I will not provide a tutorial for creating boot sounds, you can Google yourself ;)

BENCH-MARKING

Freeze or Re-Boot

1 Try increase CPU 1600 Mhz voltage by +25 mV or +50 mV. I would not recommend any more than that !

2 Lower CPU OC back to stock max 1400 MHz setting

3 To find out which frequency cause the freeze :

a) If you have UV the CPU and the device freeze, obviously you need to increase the voltage to a particular frequency step(s)

b) Do a stress test with SetCPU (or other app) and lock your max frequency for each step (DO NOT SET ON BOOT WHILST TESTING)

4 Try a different governor

5 Use a different benchmark app/tool

AnTuTu Crashes?

* Try another benchmark app !

Low Bench-Marking Scores

* Consectutive tests as well as OC may heat the CPU high enough where thermal limiting occurs. Well here you go........... I observed my CPU regularly drop to 800 MHz after hitting a thermal limit during testing.

Here's the proof !

https://github.com/UpInTheAir/P6800_JB_SkyHigh_Kernel/blob/master/arch/arm/mach-exynos/mach-px.c

#ifdef CONFIG_EXYNOS4_SETUP_THERMAL
/* below temperature base on the celcius degree */
struct s5p_platform_tmu px_tmu_data __initdata = {
.ts = {
[COLOR="Red"].stop_1st_throttle = 61,
.start_1st_throttle = 64,[/COLOR]
.stop_2nd_throttle = 87,
.start_2nd_throttle = 103,
.start_tripping = 110,
.start_emergency = 120,
.stop_mem_throttle = 80,
.start_mem_throttle = 85,
},
.cpufreq = {
.limit_1st_throttle = [COLOR="Red"]800000[/COLOR], /* 800MHz in KHz order */
.limit_2nd_throttle = 200000, /* 200MHz in KHz order */

* With some undervolt and governor tuning, little OC impact will be felt on battery. Not everyone fixes their CPU to max with performance governor :rolleyes: so, providing your hardware can handle it, some OC should be OK for everyday use as the CPU only briefly scales to max freq with the 'right' governor.

* As you can see, this could be easily changed to allow (cheat) in benchmarks. This won't make much difference to everyday use, but IMO shouldn't be touched. My silicon may not handle it

GPU init.d SCRIPTS

How to install/run :

1. Mount system/etc/init.d folder [R/W]

2. Copy your script to your system/etc/init.d folder

3. Set script permission to 777

4. Reboot

-OR-

Use root explorer app (Linux script handler) -or- script manager app to run script - no need to reboot

[Q] How do I check the script worked?

[A] Check values changed in files:

sys/class/misc/......

gpu_clock_control (gpu_control & gpu_staycount)

gpu_voltage_control (gpu_control)

[Q] How do I check it's a valid frequency?

[A] I observed the live GPU freq values in sys/module/mali/parameters/mali_gpu_clk. I use the Cool Tool app in the "label" section

ANYTHING ELSE

When I find the time ;)

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