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4.2 Benchmark Description

 

To measure the performance of this proposal, we need to see the effect it has on a set of benchmarks. Before getting into a detailed description of the benchmarks, we would like to describe the three characteristics a benchmark can have that may have a higher effect on the behavior of the proposed system.

Concurrency.
It is important to see that the number of processes in the benchmark will affect the behavior of the system. If only one process is running in the system, the application that is swapping out pages will not have to wait for another application that may have locked some of the resources it needs. No other application will try to swap in/out pages.

I/O.
Another benchmark parameter that will affect the system is the amount of file-system I/O performed by the benchmark. This I/O may conflict with the one performed by the paging system because both are done in the same disk (although in different partitions).

Compression ratio.
gif Finally, the compression ratio may affect the system in two ways. First, the better pages compress, the larger the final size of the swap area will be. Second, if pages have a good compression ratio, the number of pages that can be kept in the cache will be higher. Thus the number of disk accesses should be lower than with bad compression ratios.

Once described the most important characteristics, we will describe the benchmarks used.

Table 1 summarizes the characteristics of each benchmark according to the parameters described in the first part of this subsection.

  table137
Table 1:   Benchmark characteristics.


next up previous
Next: 4.3 Performance Results Up: 4 Experimental Evaluation Previous: 4.1 Methodology

Toni Cortes
Tue Apr 27 17:43:22 MET DST 1999