What is an atomic or indivisible operation (or instruction) and why is it necessary?
What will be an ideal response?
An atomic operation is one that must be completed without interruption. For example, an atomic test and set
instruction reads a memory location, performs a test, and then sets the result. Such an instruction cannot be
interrupted. Once started, it must be completed.
Atomic operations are used in multiprocessor and distributed systems to control shared resources. Consider two
processors and a peripheral. Imagine that each processor wants to take control of the peripheral. A flag bit in
memory indicates whether the peripheral is busy. If a processor wants the resource, it tests the flag and sets it to
claim the resource. However, if two devices each make a simultaneous request, the first device reads the flag and
sets it. The second device also reads the flag and finds it clear because the first device has not yet set it. An atomic
transaction prevents this. Once a device has started to read the flag, it may not be read by another device until
the current device has released it.
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A(n) ____ is a collection of rules that define the content and structure of an XML document.
A. data structure B. DTD C. XMLNS D. validity glossary
Answer the following statements true (T) or false (F)
1. All people who will have primary or secondary use of a system must be involved in the system design. 2. The most rapidly growing type of computing is desktop computing. 3. Parallel conversion attempts to combine the best features of parallel and direct conversion, without incurring all the risks. 4. Conversion by direct changeover means that, on a specified date, users stop using the old system and the new system is put into use. 5. Security is the responsibility of all those who come into contact with the system and is only as good as the most lax behavior or policy in the organization. 6. Conversion by direct changeover means that, on a specified date, users stop using the old system, and the new system is put into use.
To select an entire word in a document by using a touchscreen, ________ the word
A) click B) double-tap C) tap D) double-click
Briefly describe three of the seven elements of a network security policy.
What will be an ideal response?