CS501 GDB 1 Solution and Discussion

[zareen]

Fixed length instructions vs Variable length instructions.

Fixed length instructions:-

All the records in the file are of same size.
Leads to memory wastage.
Access of the records is easier and faster.
Exact location of the records can be determined: location of ith record would be.n*(i-1), where n is the size of every record.

Variable length instructios:-

Different records in the file have different sizes.
Memory efficient.
Access of the records is slower.

Large cache blocks vs small cache blocks.

The “largest” block size case is best for repeated, in-order memory accesses (best for spacial locality) and worst for repeated, random memory accesses (worst for temporal locality).

The “smallest” block size case is worst for repeated, in-order memory accesses (worst for spacial locality) and best for repeated, random memory accesses (best for temporal locality). It is good for out-of-order memory accesses, depending on the size of the working set.

Simple instruction set vs complex instruction set.

Characteristic of Simple instruction set:

The simple instruction set provides commands to the processor, to tell it what it needs to do. The instruction set consists of addressing modes, instructions, native data types, registers, memory architecture, interrupt, and exception handling, and external I/O.

Characteristic of Complex instruction set:

Complex instruction, hence complex instruction decoding.
Instruction are larger than one word size.
Instruction may take more than single clock cycle to get executed.
Less number of general purpose register as operation get performed in memory itself.
Complex Addressing Modes.
More Data types.