- The Relative Worst Order Ratio Applied to Paging.
- Joan Boyar, Lene M. Favrholdt, and Kim S. Larsen.
Journal of Computer and System Sciences, 73(5): 818-843, 2007.
The relative worst order ratio, a relatively new measure for the quality
of on-line algorithms, is extended and applied to the paging problem.
We obtain results significantly different from those obtained with the
competitive ratio.
First, we devise a new deterministic paging algorithm,
Retrospective-LRU, and
show that, according to the relative worst order ratio, it performs better
than LRU.
This is supported by experimental results, but contrasts with the
competitive ratio.
Furthermore, the relative worst order ratio (and practice) indicates that LRU
is better than FWF, though all deterministic marking algorithms have the same
competitive ratio.
Look-ahead is also shown to be a significant advantage with this
new measure, whereas the competitive ratio does not reflect that
look-ahead can be helpful.
Finally, as with the competitive ratio, no
deterministic marking
algorithm
can be significantly better than
LRU, but the randomized algorithm MARK is better than LRU.
The publication is available from ScienceDirect (subscription may be required).
Other publications by the author.
Last modified: Sat Jun 1 09:29:15 CEST 2013
Kim Skak Larsen
(kslarsen@imada.sdu.dk)