[Android General] bedalus:
Results

Over my time here in XDA I've built up a few studies on the Nexus S.

Here are the links. There are summaries in each thread in the first and second (and sometimes third) posts of the main findings, but I've done some very quick and minimal overviews here also.

ICS ROM Benchmarks: this thread

-Freely available benchmark programs were used to determine which ROMs had the best performance. Among the top six were an AOSP ROM with some CM9 parts, MIUI, and Stock, all within about 1% of each other. My conclusion was that the gingerbread tweaks we all knew and loved didn't improve performance with ICS, and in some cases, enthusiastic young developers were throwing together incompatible tweaks that hurt performance.

Battery Drain Benchmarks: this thread

#1 - With screen on, the slowest processor step saves the most power (duh... :p)

#2 - Regardless of your choice of governor, even with extreme undervolting, you are not going to be able to increase your battery life by more than 2%. (Click here for explanation.)

For the instability introduced by UV, it seems a 2% increase in battery life isn't really worth it! REMEMBER rebooting uses so much power, a single one would more than undo any savings made by UV.

Also, undervolting seems to cause more reboots when the battery is running low. This makes sense, as the battery runs low it loses some of its voltage (which shouldn't be confused with remaining power capacity).

#4 - This is one point that everyone ought to know, but I'm including because many people seem to believe in myths: if the screen is off, and the CPU is not active, neither deep idle nor UV will have any impact on battery life.

#6 - If you have an amoled display, black saves a great deal of power. After that, red. If you have a black and red theme, this is saving you power!

#9 - For amoled displays, Kernels higher FPS mods will cause the screen to drain about more power. For instance, on the Nexus S, 65 fps drained 10% more power than 56 fps. Also, 50 fps saved about 7% power compared to 56 fps.

#11 - If you've got no reception, you might as well be in airplane mode, because searching for reception also eats battery.

#12 - If your phone can't handle OC (or UV for that matter) it's because components in general are built to cost, which means factoring in tolerances, and every chip is made as cheaply as possible within the specified tolerances. Outside of those tolerances, whether your chip can cope or not is unfortunately down to the whether you got lucky with the individual device that dropped off the manufacturing line.

ARM document on A8 fault tolerance: http://infocenter.arm.com/help/index.../Babhjhag.html

In fact I measured how UV in particular can cause errors, and saw in action the A8 using MORE power to correct the errors.

CPU Governors and I/O Schedulers: this thread

-Interestingly, CFQ generally performs very well, and deadline. Most custom kernel developers in the Nexus S section recommend a version of deadline that has been tweaked for flash storage. In one of my unpublished benchmarks deadline performed slightly better than CFQ.

Does SuperCharging work?: this thread

-This was just a short study to find out if this script is suitable for the Nexus S, but it turned out it had no effect, positive or negative. This script was probably more use on devices that had less memory. One benefit that remains is to 'bulletproof' the launcher.

Kernel Memory Allocators: this thread

-This is another short study for kernel developers to show that SLUB performs best.