What are the parameters for measuring the efficiency and performance of a computer system?

Answer 1

1. effectiveness of the system if whether it achieves its goals or not.
2. efficiency , check if what is produced is it the product that was supposed to be produced.
3. complexity ,checking on how the system elements are complicated .
4. control ,operate under the given instruction.

Answer 2

Metrics

are criteria to compare the performances of a system. In general, the metrics are related to speed, accuracy, reliability and availability of services. The basic characteristic of a computer system that we typically need to measure are:

• I a count of how many times an event occurs,
• I the duration of sometime interval, and
• I the size of some parameter.

Since many performance metrics turn out to be misleading, people have designed benchmarks I Example: SPEC Benchmark I Integer benchmark I Floating point benchmark I These benchmarks are typically a collection of several codes that come from “real-world software” I The question “what is a good benchmark” is di

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cult I A benchmark is representative of a given workload. If the benchmarks do not correspond to what you’ll do with the computer, then the benchmark results are not relevant to you

I other typical benchmarks I Livermore loops, NAS kernels, LINPACK . . . I SPEC SFS, SPEC Web . . .

A Monitor

is a tool to observe the activities on a system. In general, a monitor:

1 makes measurements on the system (Observation)

2 collect performance statistics (Collection),

3 analyses the data (Analysis),

4 displays results (Presentation).

Observation

is commonly performed with three mechanisms:

• Implicit spying it is sometimes possible to spy the system without really interfering with it (listening on a local Ethernet bus or in wireless environments). Thus, there is almost no impact on the performance of the system being monitored. Implicit-spying is generally used with filters because many observed data are not interesting.
• Explicit Instrumenting By incorporating trace points, probe points, hooks or counters, additional information’s to implicit-spying can be obtained. Some systems o

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  er an API to incorporate such hooks or exports the values of internal counters.

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Probing Making “feeler” requests on the system to sense its current performance. Some activities can be observed by only one of the three mechanisms.