The Exokernel Operating System and Active Networks - Advanced Operating Systems and Kernel Applications - page 154

tion possible. In order to optimize an operating
system, the system must first be flexible enough
to be optimized. An operating system that is ex-
tensible is by its very nature open to changes and
therefore easy to optimize. Although traditional
operating systems can be optimized, they lack
the flexibility required to make the changes easy.
Because extensible operating systems are easy to
change, they are perhaps the best design to work
with when trying to optimize an operating system.
Therefore, we still maintain that it is extensibility
that is the foundation of being able to optimize
operating systems.

them, then modern operating system designers
need to embrace the extensible approach found
in the Exokernel.

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concluSion

As we bring our discussion to a close, we recall
the two forces that are stretching the capabili-
ties of the modern monolithic operating system.
On one side there is the need for the operating
system to be more flexible to accommodate new
technologies. On the other side is the need for
the operating system to become faster so it can
keep pace with faster hardware and faster com-
munication speeds. Our discussion showed how
an extensible operating system like the Exokernel
might fulfill both needs. Extensibility allows an
operating system to be flexible enough to meet
the changing demands of new technologies, while
also making optimization easier, which translates
into faster operating systems that can keep pace
with faster computing environments.
In conclusion, there is a need for a faster and
more flexible operating system, and the exten-
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this need. The speed and flexibility offered by
the Exokernel will help operating systems avoid
being the performance bottleneck in computer
systems for years to come. Although extensible
operating system technology is still in its infancy,
the initial findings are encouraging to researchers.
If contemporary operating systems are to keep
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