Analysis of space allocation in a generally fragmented linear store

Summary

The space allocation process in a fragmented linear store with general fragmentation characteristics is analysed. For a given allocation requirement t, exact expression for the n-th moment of the allocation penalty for single block contiguous allocation is obtained, which for large t is shown to be O(¯F(t)⁻ⁿ), where ¯F(·) is the complementary distribution function of the free block sizes. For multiple block non-contiguous allocation, it is shown that the corresponding penalty can be approximated by an n-th degree polynomial and is O(t ⁿ) for large t. Compared with experimental values, the model results are able to achieve good agreement.