Compare the storage needed to keep track of free memory for
Compare the storage needed to keep track of free memory for the following three meth-
ods: bitmap, linked list and linked list with H entries stored in holes. Determine the storage needed to keep track of free space for a 1 GB
memory with
1. a bitmap (allocation unit size is n bytes),
2. a linked list (an alternating sequence of m bytes segments and holes assumed, each
node consists of a 32-bit address, 16-bit length, 16-bit next node elds), and
3. a linked list with H entries stored in holes (H entries are not counted).
Under which condition one is better than the other?
Solution
the storage neededto keep track of free space for a 1 GB
memory with
1. a bitmap (allocation unit size is n bytes), for 1 gb it needed 1024*1024*1024 bytes
if it\'s adress bus is less than 64 bit , this method is not good it less perform than 2nd method
2. a linked list (an alternating sequence of m bytes segments and holes assumed, each
node consists of a 32-bit address, 16-bit length, 16-bit next node elds),
for 64 bit processor this method is adavantageous , because it uses efficiently, if the adress bus size is less than 64 bit this perform very bad.
3. a linked list with H entries stored in holes (H entries are not counted).
this method gives least performance than 1st and 2nd.because it uses additional storage for H entries.
