difference between exokernel and microkernel

[stickmansquark]

I have been looking into stuff on the mach and l4 microkernel, and I think they are pretty cool. But anyway, when I was on the page for them on wikipedia, exokernels were mentioned. I looked exokernel and the definition I recieved appeared to be the same. Can somebody please explain the difference?

[MoonWolf]

Looking for inforamtion trough google: (three searches less then 2 min)

Define: Exokernel
# A system kernel that strives to only provide essential functions. This allows programs to manage their own resources, theoretically increasing the speed and efficiency of the program.
tunes.org/~unios/terminology.html

# In computer science, the kernel is the fundamental part of an operating system. It is a piece of software responsible for providing secure access to the machine's hardware to various computer programs. Since there are many programs, and access to the hardware is limited, the kernel is also responsible for deciding when and how long a program should be able to make use of a piece of hardware, in a technique called multiplexing. Accessing the hardware directly could also be very complex, so kernel
en.wikipedia.org/wiki/Exokernel

Define: Microkernel
# A kernel implementing a minimal set of abstractions. Typically, higher-level OS services such as file systems and device drivers are implemented in layers above a microkernel, possibly in trusted user-mode servers. Mac OS X is a hybrid between microkernel and monolithic kernel architectures. See also monolithic kernel.
developer.apple.com/documentation/Darwin/Conceptual/KernelProgramming/Glossary/chapter_21_section_1.html

# A system kernel that runs itself in protected memory space, and all drivers and processes in a seperate memory space allowing for (theoretically) better stability.
tunes.org/~unios/terminology.html

define: monolithic kernel
# A kernel architecture in which all pieces of the kernel are closely intertwined. A monolithic kernel provides substantial performance improvements. It is difficult to evolve the individual components independently, however. The Mac OS X kernel is a hybrid of the monolithic and microkernel models. See also microkernel.
developer.apple.com/documentation/Darwin/Conceptual/KernelProgramming/Glossary/chapter_21_section_1.html

# In computer science, the kernel is the fundamental part of an operating system. It is a piece of software responsible for providing secure access to the machine's hardware to various computer programs. Since there are many programs, and access to the hardware is limited, the kernel is also responsible for deciding when and how long a program should be able to make use of a piece of hardware, in a technique called multiplexing. Accessing the hardware directly could also be very complex, so kernel
en.wikipedia.org/wiki/Monolithic_kernel

Reading only the most relative parts of the information found 5 min max: (your reading speed may differ)

Exo: A system kernel that strives to only provide essential functions.
Micro: A system kernel that runs itself in protected memory space, and all drivers and processes in a seperate memory space
Mono: A kernel architecture in which all pieces of the kernel are closely intertwined.

Comprehending information: less time then it took to look for it. (your speed may differ)
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The information in my post could verywell be wrong since
a. I took minimal time to look for information
b. I did never double check
c. I know very litle about kernels