Techniques of management

There are different techniques for handling memory, including the following:

• Single allocation: All the memory, besides the part reserved for the OS, is available for the application. This means that there can only be one application in execution at a time, like in Microsoft Disk Operating System (MS-DOS).
• Partitioned allocation: This divides the memory into different blocks called partitions. Using one of these blocks per process makes it possible to execute more than one process at once. The partitions can be relocated and compacted in order to obtain more contiguous memory space for the next processes.
• Paged memory: The memory is divided into parts called frames, which have a fixed size. A process' memory is divided into parts of the same size called pages. There is a mapping between pages and frames that makes the process see its own virtual memory as contiguous. This process is also known as pagination.