[AT&T Samsung Galaxy S II Skyrocket SGH-I727] faux123:
NOTICE: This is COMPATIBLE with ALL Samsung Rooted Stock and Custom ROMs

For frequency control use fauxclock from Google Play

Just a statement regarding kernel source: The Kernel Source is of course covered under GPL version 2. Free software does NOT mean no work or time was spent working on it. I have donated a large sum of my free time to hack this kernel. If you use my modified kernel source in parts or in its entirety, I kindly ask you mention its origins and to send me a github pull request or PM whenever you find bugs or think you can help improve my kernel hack further. This way the entire community will truly benefit from the spirit of open source. Thank you!​

Hi XDA members and fellow Samsung users:

This is my sixteenth kernel hack. I want to thank my Team Kang tea mates Roman, Whitehawks and CMenard, and several others I cannot recall for inspiring me to venture into this unfamiliar territory for me.

What is a Kernel? The Kernel is the Foundation in which everything else builds upon in any software system.

[Car Analogy]: Kernel is like the Engine, Electrical system and the Transmission to a car. The Library, Framework and the Apps [AKA ROM] are the body frame and the rest of the Car.

​

THIS KERNEL is BASED ON Samsung Source Code. So it is COMPATIBLE ONLY WITH Samsung Gingerbread Builds.

Please DO NOT use any task killers, they DO NOT improve performance nor battery life. They INTERFERE with your phone's stability (more crashes) and App compatibilities (Forced Close).

CleanCache (via ZCache backend)

ZCACHE is a new technology I introduced to Qualcomm Kernel. ZCACHE is a compressed cache similar to ZRAM but the similarity ends there. ZCache is meant to provide as many "cleancache" pages (non-dirty or untouched "virgin" memory) to apps that request for new memory. CleanCache is very easy to allocate and no additional penalty are required to hand them out, so having more CleanCache pages will improve performance. Under heavy memory pressure, often times the kernel will NOT have enough CleanCache pages, so the kernel has to do EXTRA work to reclaim dirty cache pages and clean them for the new apps that's requesting for them. The described process creates a performance hit for the kernel and the app, so the idea is to use compression to create more CleanCache pages available for use. Of course there's a penalty to pay for using compression, but the trade-off between compression penalty and the penalty for reclaiming dirty cache pages and allocating them after cleaning is smaller for compression, so in the end, CleanCache should add more performance.

ZRAM (aka CompCache aka RAMZSwap)

ZRAM is an updated version formally known as CompCache and RAMZSwap. It was originally designed for 2.6.38.xx kernels, I have backported to our 2.6.35.xx kernel. ZRAM allows real-time compression of memory objects in RAM thus reducing memory pressure for the Linux kernel and can keep more apps in memory longer (more apps in RAM == better performance, less fetching from slower MMC or SDCard). Compression, however, is not Free. Some CPU cycles are required to do the compress/decompression, so there's a slight penalty for it. The original CompCache / RAMZSwap required a user space binary to control its behavior which adds additional penalty to performance, but the new version ZRAM eliminated the need for a separate dedicated daemon, thus reducing the overhead and increased performance from the old CompCache by 20%. Therefore, with the newer implementation of ZRAM interface, the performance penalty is almost negligible. :D

Joe's RCU (Optimized for Small SMP systems - NOT YET ADDED)

Joe Korty has created an RCU for small SMP systems (> 32 cores). His approach is to isolate all the Garbage Collection (GC, a slow time consuming but necessary processing) to a single core, thus allowing other cores to ONLY work on real required processing. This will allow the additional cores to complete their assigned tasks as fast as possible (not bogged down by GC) then immediately go back to a suspended state (saving battery).

Fast No Hz RCU (Optimized for SMP operations)

Fast NoHz is an optimized version of the traditional Tree RCU. Many new kernels are using the Tickless NoHz design. This RCU is tailored and designed to work with the new NoHz kernel system.

SmartAssV2 Governor (Balanced - NOT COMPATIBLE WITH QUALCOMM 8x60)

This governor has a built-in "profile" similar to SetCPU, so screen off will use lower clock rate thus conserve more battery, but it also has a fast wake up feature so that user interaction will not see the lag when switching from Sleep to Wake state.... (So SetCPU Profiles are sorta redundant when using this governor, you can still use SetCPU to OC to higher than default Clock frequency).

Interactive Governor (Performance - NOT COMPATIBLE WITH QUALCOMM 8x60)

This governor is designed to put more priority to User Interface (UI aka Apps) tasks, therefore appears more responsive then the traditional OnDemand governor. So if you want the smoothest UI interaction, this governor is for you...

Brain F*ck Scheduler - (BFS - NOT COMPATIBLE WITH QUALCOMM 8x60)

This scheduler is designed to be simple and speedy tailor specifically for user interface type systems such as desktop/smart phone devices where user interaction is MORE important than serving 1 million web requests (CFS, the default scheduler) at the same time (think of nimble desktop workstations vs large corporate servers).

SLQB - (SLAB allocator with Queue)

This memory allocator is designed for small number of CPUs system (such as desktop or smart phone devices). This allocator is design to be simple and it is optimized for using order-0 pages as much as possible (order-0 pages are the simplest therefore quickest type of memory in a Linux system to allocate). Not all kernels are using SLQB including CM7 main line...

Fair Budget Queue (BFQ I/O scheduler)

This I/O scheduler is an improvement on top of Completely Fair Queue (CFQ). CFQ is fair in terms of time but not in terms of throughput / bandwidth, so BFQ make sure that both time and throughput / bandwidth are balanced across all requests.

Installation Instructions:

Here's a step by step instruction to install this kernel:

[ CFS ] (Mainline Edition - should work with ALL phones!)

The File ==> Skyrocket kernel 010m (1.73 GHz, L2 speed up to 1.56 GHz) <==

[ CFS ] (Ultimate Edition - should work with most phones but NOT GUARANTEED!)

The File ==> Skyrocket kernel 010u (1.73 GHz, L2 speed up to 1.56 GHz, GPU 3D @ 320 MHz, GPU 2D @ 220 MHz, CleanCache Enabled) <==

1. download the above file (via phone directly or to a PC)

2. copy the downloaded zip file to /sdcard/download/

3. Open ROM Manager and select "Reboot into Recovery" and select "OK"

4. Once in recovery, select "wipe cache partition", select "Yes", then select "advanced", then select "Wipe Dalvik Cache", then select "Yes" again. Once finished, click the back button to go back to the main recovery menu. On that menu, select "Install Zip From SDCad", then select "Choose zip from SDCard", then go to /sdcard/download and select the downloaded zip file and let it run its script.

5. Once the script is done, select "reboot system now"

Note: After FLASHING, the first reboot may take longer than usual, please be patient... After the first reboot, it may lag during initial load (let everything finish loading). Once everything is loaded and phone is ready for use, reboot the phone a 2nd time and the lag will be gone and everything should be silky smooth... [/b]

[ Advanced Users: ]

[ Optional: ]

[ For Kernel Devlopers ONLY: ]

The File ==> My Global VDD_TABLE for under volt patch <==

Optional Under voltage:

[ to over volt ALL frequencies by 25000 uv (microvolts) ]
echo "+25000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
[ to under volt ALL frequencies by 25000 uv (microvolts) ]
echo "-25000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels

[ to set a specific frequency (ie 1.18 GHz)
with a specific voltage (ie 1.0875 volts) ]
echo "1188000 1087500" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels

CPU Frequency Voltage Table Example

192000: 812500
310500: 812500
384000: 812500
432000: 812500
486000: 837500
540000: 850000
594000: 862500
648000: 875000
702000: 900000
756000: 925000
810000: 937500
864000: 962500
918000: 962500
972000: 962500
1026000: 975000
1080000: 987500
1134000: 1000000
1188000: 1012500
1242000: 1025000
1296000: 1050000
1350000: 1075000
1404000: 1100000
1458000: 1112500
1512000: 1125000
1566000: 1150000

Optional: Stock Clock Frequencies for Dual CPUs

su
echo 192000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
echo 1188000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq

echo 1 > /sys/devices/system/cpu/cpu1/cpufreq/online
echo 192000 > /sys/devices/system/cpu/cpu1/cpufreq/scaling_min_freq
echo 1188000 > /sys/devices/system/cpu/cpu1/cpufreq/scaling_max_freq

NEWS BULLETIN:

Version 010 is OUT for skyrocket variant!

Please don't hesitate to talk among yourselves and help each other out... The XDA community is what inspired me to hack kernels for everyone since everyone here is nice and helpful to each other... Keep helping each other.... Famous proverb: It's better to give than to receive...

BUGS:

Not All CHIPS ARE CREATED EQUAL

TO DO:

version 1.x.x -- Haven't thought about it yet...

History:

See Post below...

Standard Disclaimer: Not responsible for bricking your phone, voiding your warranty, or any other pain or suffering you may feel as result of using this kernel!!!

My github Complying with GPL and XDA rulez :D

Follow me on :

If you find this Kernel useful, feel free to hit the [Thanks] button below