Database Reference
In-Depth Information
Figure
8-1
represents the increase in the number of helpers to the gift-wrapping process. It becomes evident
that after a certain point, with a fifth person, more gifts are wrapped. The curve continues to show an upward growth
until an eighth person is introduced, when the curve slowly starts to dip. This is because of skewing: the curve starts
going down, indicating more time to complete the operation. This is an example of the law of diminishing returns.
Too much of something may bring back a lesser satisfaction or benefit. A similar behavior will also be noticed in the
example related to information technology.
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# of people
Number of Gifts
Figure 8-1.
Parallel processing example
Parallel processing is the
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division of work into smaller tasks, that is, to divide and conquer
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assignment of many smaller tasks into multiple threads to execute simultaneously
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reduction of wall-clock time for execution of computer programs.
Why Parallel Processing?
There could be degraded performance of the system due to an increase in the number of users and contention for
resources. When this occurs, one solution explored in Chapter 4 was to increase the processing power of the computer
by adding additional resources such as CPU and memory, that is, vertically scaling the hardware. Although this is
not ideal in most situations, it does potentially help provide a temporary solution toward supporting the increase
in the number of users. Another solution was to add additional servers and scale the number of users in a linear
or horizontal fashion. This would allow for distribution of users across multiple machines, thus providing linear
scalability and availability.
If we had one large complex process and a computer with a single processor, this would take time to complete
depending on many other factors. In this situation, one option is to increase the speed of the existing processor (like
increasing the resources such as number of CPUs or CPU power or memory on the current hardware) to accept more
workload. A given processor is made to specifications, it is made to perform at a certain speed; the same processor
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