[KERNELS][ICS][I9000] The ICS Kernel Benchmarking Project -Update: Devil

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Goal of this little project is to dispel myths and hearsay and trying to assess the elusive performance of custom kernels for our beloved SGS I9000.

So far this has proven quite challenging as there is no single good benchmark on Android (yet):

• a lot of people have been misled by ridiculous Quadrant scores: ridiculous because, with some small tweaks which do not affect real performance in any way, shape or form, it is possible to boost the Quadrant score by factor 3x.
  You're free to believe that your SGS I9000 which scores 3000+ on Quadrant is faster than a SGS II, but then please leave this thread and move on.
• some kernels may seem smooth with some games, and get high scores on some synthetic benchmark, yet the UI appears "laggy" and stutters a lot in comparison to other kernels which score lower on the same benchmark
• some popular benchmarks give results with unacceptably low reproducibility, i.e. if you run them multiple times without changing a thing on your system, you get scores varying by 50% of more, in a completely random fashion
• most popular benchmarks do not measure or take into account multitasking and CPU contention with other applications, yet on a typical usage one has background tasks such as the media scanner or synchronization which kick in often and unpredictably

So this will be mostly a work in progress, i'm testing several benchmarks and several kernels in multiple combinations, trying to analyze which benchmarks offer certain criteria which make them useful, namely:

• Reproducibility of results: running the same tests multiple times, should result in a very small variance of the final score
• Performance separation: benchmarks which are too "synthetic" and show only a dependency on clock speed are not useful to discriminate "fast" kernels from "slow" kernels
• Performance representation: we all know when a kernel "looks" or "feels" fast or smooth. If a benchmarks shows you that a "laggy" kernel scores higher than a fast and responsive one, it's likely that the benchmark is not well designed

I'll work more on this thread explaining my (current) choice of tests and what they're good for.
But for now i'll just post a link to the summary table, and give a brief recommendation concerning popular ICS kernels; recommendation which i'll explain in the coming days.

Base ROM:
Slim ICS 2.8
(because is fast, smooth and has the least background stuff of all ICS ROMs which i tested)

Test Conditions:
Whenever possible, i tried to overclock the kernels to 1.2GHz which most / all phones should have no trouble achieving.
In case of Semaphore i had to use the bus / live overclock but it wasn't fully stable at 1.2GHz on my phone so i ran most of the tests at 1.14GHz.

Tested Kernels:
Stock Teamhacksung V17
Devil 1.1.6b BFS
Devil 1.1.6b CFS
Icy Glitch V14 b
Semaphore ICS 0.9.5b

Recommendation:
Devil 1.1.6b CFS, Icy Glitch V14b (with SmartassV2 and FIOPS), and Midnight ICS (with a tweaked Conservative) are trading blows for the fastest kernel.
At the time of testing, Midnight is slightly worse in terms of overclocking though, apparently due to different voltages, also it doesn't allow overclocking beyond 1.2GHz.
But what's interesting is that it achieves great performance while using a tweaked conservative governor.

Devil 1.1.6b BFS is good but obviously inferior to its CFS brother.

Semaphore has the lowest cache and memory latency in the multithreaded test, it also has impressive sd card read speed and in general appears super responsive, but it's a bit worse in 3D gaming and especially it lacks "true" overclocking, "live overclocking" changes the bus clock and is way more unstable, in fact on my phone i couldn't run it stable at 1.2GHz.

All kernels are significantly faster than the stock teamhacksung's kernel, so you have no excuses not to upgrade to one of the popular custom kernels!

ICS 4.0.4
Started testing Android ICS 4.0.4 kernels on Slim ICS 3.2.
All tested kernels are "huge mem" versions with 380+MB of available RAM, without breaking video playback or 720p recording.
Summary:

• the stock kernel from Teamhacksung is now a very respectable performer, unless you plan to overclock probably you don't need to install one of the other kernels
• Semaphore, Midnight and Devil are all very fast and smooth

Results table:
https://docs.google.com/spreadsheet/...FpJejFPWDh5S1E

Res 1

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One request for the kernel developers:
could you please post me what are your preferred / recommended settings in terms of Governor and I/O Scheduler?

Only one configuration per kernel please, as running these tests is rather time consuming.

Test Settings

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So for anybody who wants to follow the same methodology as I used to test kernels, please pay attention that in some tests i didn't use stock settings, to try to improve the reproducibility of the results.

Before all test, i put the phone in flight mode, and disable all synch services.

Antutu: DB I/O and SD Write and Read have poor reproducibility. So i run these tests separately 5 times, and take the best scores.

RealPi: the number of iterations is increased by factor 10x i.e.: 100000 digits

MPAC: lots of customization here. Also be careful as it's not very stable and some settings will make it crash.
All tests: 8 threads (or 8 producer / consumer pairs)
CPU: 10000000 iterations, use case: integer (i'm considering to add logical too)
Memory: stock apart for nr of threads. Repeat the test 5 times and get best numbers
Cache: 40 iterations

Res 3

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With this should be enough.

Judging from those results, CFS Devil looks really promising.

Semaphore live oc stability issues happen only on Slim ICS indeed. On ICSSGS I have perfect stability at 1.2 ghz. And performance is just great, paired with very good battery life.

GT-i9000 / ICSSGS 4.2 / Semaphore 0.9.0

A quick question: did you lock the max freq to eliminate the "governor" variable?
Because each kernel could have governor's tweaks that the other don't.

Based on what you posted here, the differences between Glitch and Devil is practically none.

I tested both and didn't feel any tangible difference, in the end, it comes down to the unique features of each kernel.

Overclocking bus vs adding an extra step aren't even slightly comparable. Maybe do tests not overclocked?

Also there is a new glitch build with 100% working bln.

Sent from my GT-I9000 using xda premium

+1 for tests without overclock. Majority of us, users do not overclock. Maybe a seperate test for overclocking could be nice , but comparisons should be done with stock speeds imho.

Thanks for the time and effort. We needed this.

Overclocking bus Vs adding an extra step isn't an apple to apple comparison, I agree.
However my goal was to use each kernel in the best possible way, and if some kernels have the possibility to use higher multipliers / extra frequency steps, that is an advantage for the user, compared to the kernels who only offer live overclock.

Don't get me wrong, i love Semaphore and i've been using it for a long time.
And i have no doubt that some users can get it stable with live overclock to 1.2GHz.
But that is the ceiling, while with other kernels even my phone can reach stable overclocks of 1.5GHz, and that is something to consider.

I chose as the basis for my tests an overclock of 1.2GHz because it's something which practically everybody can use, without massive battery drain, overheat or shortening the life of the device.

I'll try to add measurements at stock speeds for those who don't like to overclock.