In fixed portioning scheme, what are the advantages of using unequal- size partitions?
With unequal-size partitions there are two probable ways to assign process to partitions. The simplest way is to assign every process to the smallest partition within which it will fit. In this case, scheduling queue is required for each partition, to hold swapped out process destined for that partition. The benefit of this approach is that processes are for all time assigned in such a way as to minimize wasted memory within a partition.
There are two difficulties with the utilize of equal-size fixed partition:
- A program may be excessively long to fit the partition in such a circumstances the programmer have to design the program with the use of overlays thus that only a portion of program needed in the main memory at any one time. When a module is needed that isn't present, the program should load that module in to the programs partition, overlaying whether data or programs are there.
- Main memory utilization is wasteful. There is wasted space internal to a partition because of the block of data loaded is smaller than partition called internal fragmentation.
Both of these problems are able to be lessened, by use of using un-equal partition. This teqnique is most favorable, for individual partition. The utilization of unequal-size partition provides a degree of flexibility to fixed partitioning.