noob and understanding kernels

[spacecasespiff]

I'm new to the kernel thing and have a little bit of an understanding of what the are but have more questions

There are a few kernels out but I don't know what makes each on different from the others. I don't know what to look for in a kernel. What makes one better then the next, what should I look for.

 

[davey11]

I have heard the analogy describing kernels as the kernel is the engine in a car and the frame, body etc are the rom.

The kernel takes commands from the rom and translates those commands onto the hardware.

When looking at a forum post about a kernel and how the developer describes it, admittedly it is filled with arcane jargon and techy mumbo jumbo its hard to decide which to choose.

My take on all this is almost a case of blind trust. I flash em to try em and see which one I like. I have flashed at least 5 different ones and they all were fine. These guys do not post something without heavy testing. Their reputation is at stake and the last thing they want is a faulty piece of software.

 

[jackrv]

I wonder the same thing, but I do have a question... I could be wrong here in the context of terminology on mobile devices vs desktops, but Kernel is basically the low-level OS. Even among different ROMs, the Kernel should be the same (or similar) as it has to support the specific hardware. (Unless some developer is good enough to compile a newer kernel to the Nexus Hardware and/or add the correct drivers). The rest of the ROM is the userland space. Launchers, UI modifications, memory and battery tweaks based on what software runs in background processes...

Kernel is the base OS + hardware drivers. If you are familiar with Windows or Mac OS X, the kernel is like NTOSKRNL.EXE for Win or XNU for Mac. It handles memory, I/O, and all low-level operations.

To add to the OP's post, do custom ROMs really use user-modified Kernels, or just optimizations of the userland environment (task-switchers, modification of programs that run on startup, etc...)?

 

[holysnikey]

jackrv is spot on with his description of what a kernel is in terms of Android.