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Unit 8: File Management
containing addresses of another n free blocks. The importance of this implementation is that Notes
addresses of a large number of free blocks can be found quickly.
Figure 8.11: Free-space Management by Free List Grouping
8.10.4 Counting
Another approach is to take advantage of the fact that, generally, several contiguous blocks may
be allocated or freed simultaneously, particularly when contiguous allocation is used. Thus,
rather than keeping a list of free disk addresses, the address of the first free block is kept and the
number n of free contiguous blocks that follow the first block. Each entry in the free-space list
then consists of a disk address and a count. Although each entry requires more space than would
LOVELY PROFESSIONAL UNIVERSITY 155
