Access Patterns

  The News Cache has been installed at Technische Universität Wien and the whole campus had the possibility to test the News Cache. Unfortunately we had only a very slow machine (the Intel 486 machine shown in section 7.3 in environment 2) for the test of the News Cache. This may be the reason why the News Cache has only been used by few people. Additionally those people had rather different interests. Hence we expect higher hit rates in situations where the users must use the News Cache.

 

Total OverviewDB Groups Articles

Requests 14016 947 10950 1392

Misses 9221 352 7436 1183

$$\% 34\% 62\% 32\% 15\%$$

 

Table 7.1 shows the results of our test phase. With more accesses to the News Cache we expect to get higher hit rates, especially when people from similar departments access the News Cache. With a higher use of the News Cache we expect hit rates of approximately $65\%$.

The users of the News Cache have been accessing 217 different newsgroups, where the top ten newsgroups make over $50\%$ of the total accesses. This proves that there is some locality in the references to newsgroups even if people with different interests access the News Cache.