[Samsung Galaxy SL i9003] loSconosciuto:
As you may know, what a CPU governor does is to decide when the current frequency needs to be changes and what's the target frequency. These decisions mostly depend on the current CPU load: high load -> high freq.

What power HAL does is to require a high CPU frequency regardless the load. This mostly happen on user interactions (ie: the screen is touched)

Its aim is to provide a smoother experience, because basically it's trying to predict high CPU loads. The downside is that sometimes the CPU is boosted for no reasons.

For example if you touch the screen to scroll a page, when the scrolling starts the CPU is already at a high freq and there won't be probably initial lags. If you tap the screen, just for the sake of it, the CPU will be boosted for no reasons (by default a CPU boost will last 500ms).

I think it's part of the project butter.

The only governor with a boostpulse interface between those included is ondemand. The other governors included most likely will never have a boostpulse interface.

Try to use ondemand with and without power HAL. You can "see" the difference with CPU Spy. 800MHz will be used a lot when power HAL is present (you can change the boosting freq from the advanced settings).

By the way I updated ondemand, it's faster than in the original kernel.

Try to use Deadline for a while. I tweaked it to better perform on flash devices. Anyway I don't think that changing I/O scheduler will make a tangible difference.

All our kernels based on the sources released by Samsung use a prebuilt module for WiFi. Dhiru tried to use the opensource driver, but it didn't work.

This prebuilt module, taken from our stock ROMs, requires a prebuilt and modified wpa_supplicant which is not completely compatible with Android 4.0+ (Samsung didn't give us the changes required to make the opensource one work). To make things worse there's dhcpcd, we have to use an old version because of the old wpa_supplicant.

In other words: it sucks.

With some access point there are no issues, with others WiFi works, but not so well and with some others nothing works.

EDIT:

Now that I think of that, there are maybe some differences when this kernel is used. I took the prebuilt module from XXLE4 instead of taking it from EDIT2: XXKPM

The warning message I get the first time I turn WiFi (maybe it happens even with the other module, I didn't try it) on suggests me that something was changed in XXLE4, but I don't know if this is a good thing or not.

I'm starting to think the problem is CWM. For now only you and spacebar2011 had issues. I will PM you something when I'll have some free time to find the problem. If nothing works, I'll just give you the tars to flash the kernel with ODIN as I did with my signal fix kernel.

@Hetalk

Thanks for trying to help, but he is a peculiar situation. The problem is not the updated blob or a wrong flash, he (and spacebar2011) tried to flash my signal fix kernel several times over a clean CM10 with no success.

Dunno, battery life had never been exceptional for me. If you use your phone a lot, any kernel will give you a bad battery life. You can see differences only if you keep your phone most of the time in idle, with mobile data disabled.

As I wrote in note [3]:

DeviceParts: System Settings > Advanced

It's not in the app drawer.