Comp111 - Quiz 2 Review
Quiz 2 Dec 8, 2009 - closed book
Quiz 2 topics
- Lectures 1-17.
- Stallings chapters 1-11 (skip material on Windows)
- Assignments 1-4.
Please fill in the blanks. Each blank is worth 5 points.
- There are three important statistical distributions
important in modelling operating systems.
distribution models inter-arrival times for events.
Its cumulative distribution function is
distribution models service times for
individual processing requests.
These distributions are both
service times for
requests do not affect the service time for the next request.
- In Kendall notation, an M/M/infinity queue is one in which
arrival times are ________6________,
service times are ________7________,
and there are an infinite number of ________8________.
- Suppose we have an M/M/1 queue with arrival factor λ and
service factor μ. This queue has a stable behavior if
________9________>= 1. (both blank 9's have same answer).
In the latter case, the queue length
________11________ without bound.
- A monitor differs from a semaphore in two ways:
- It does not ________12________ signals; uncaught
signals are ________13________.
- It is tied (via a programming language) to a specific
________14________. It is not possible to erroniously
utilize a monitor to access a different one.
- A(n) ________15________ tells the operating system that
attention is needed for a device or peripheral; a(n)
________16________ tells a process that attention is needed.
The operating system cannot receive a(n)
________16________ any more than a process can handle
- Process memory is naturally divided into
________17________ that contain
________18________, each of which
contains a fixed number of bytes. A typical byte of memory can
be divided into three bit fields including a(n)
and word address.
Inverted page tables provide a(n)
________19________ efficient mechanism for memory mapping
________20________ page tables, because the number of
pages kept in memory is often far less than the total number of
virtual pages available.