Some questions about the Android kernel

advertisements

I am new to android kernel and Mobile Operating Systems and I have a few questions regarding android kernel.

1) Does Android OS has Kernel Mode and a User mode like Normal desktop OSs ? Also does it support things like Virtual Memory ? Also I heard about Dalvik VMM. Is a copy of dalvik VMM created for each and every process ?

2) Another Question is I heard android creates a separate file system for each and every process(every application). Is this true ? If so How OS maintains these file systems and where are they mounted. Does it have a hierarchy like Unix based systems ?

3) Another Question is regarding IPC in android. What are binders in android ? How does it differ from normal IPC mechanisms like pipes, msg queues etc.

4) Another Question not related to android but How does the driver address Flash based disks like Solid state drives etc. For ex: normal HDD block can be identified by cylinder, sector and a track.


1. The "Android kernel" is the Linux kernel.

1a. No, you didn't hear about the "Dalvik VMM", you heard about the "Dalvik VM", which is simply a new kind of Java VM. It runs Java apps. No magic. No, there isn't somehow a Dalvik VM associated with "every process", but yes, each application runs in an independent process.

2. No. There's a directory structure, not distinct filesystems.

3. Why Binder?

4. Android uses the usual Linux MTD and MTD-Block devices. And the world is LBA, whether for flash or hard drives. CHS is only for those time-travelling thirty years to the past.