Partition Allocation in Memory Management

Operating systems must have memory management, which is responsible for allocating and controlling memory resources to active processes. Memory in a computer system is split up into several partitions, each of which is dedicated to a different process. Partition allocation is the name of this procedure. Several partition allocation techniques can be applied while managing memory. We shall examine the various partition allocation techniques in this post, as well as their benefits and drawbacks.

Partition Allocation Methods

Fixed and dynamic partition allocation techniques are the two primary categories of partition allocation methods used in memory management. The fixed partition allocation approach includes creating fixed-size partitions from the RAM that is currently available. A process is allotted a certain partition, and that process is only permitted to use the memory that the partition has been given. On the other hand, the dynamic partition allocation approach divides the available memory into segments of varying sizes. Processes may be given access to these partitions as necessary.

Fixed Partition Allocation Method

The simplest type of partition allocation is the fixed partition allocation technique. With this technique, the operating system creates fixed-sized memory divisions and allows them to other processes. A single process is given ownership of each partition, and that process is only permitted to use the memory in that partition. This approach is utilized in systems with less memory since it is simple to put into practice.

The fixed partition allocation method's simplicity and ease of use are two of its benefits. Complex algorithms are not necessary for this approach to allocate memory to processes. Nevertheless, this approach has several drawbacks, including the potential for memory loss. The leftover memory cannot be used by any other process if a process does not utilize the entire size of the partition that was assigned to it.

Dynamic Partition Allocation Method

A more adaptable form of partition allocation is the dynamic partition allocation method. The operating system uses this technique to split the available memory into varying-sized chunks. A process can be given access to each partition and utilize the memory contained therein. Memory can be assigned to another process after a partition has been used up by one process.

The fact that the dynamic partition allocation approach is more effective than the fixed partition allocation method is one of its benefits. Due to the flexibility of this approach, memory may be used more effectively. Partitions can be allocated and released as required. The fact that this technique needs more complicated algorithms to allocate memory to processes is one of its drawbacks.

Best-fit Allocation Method

A dynamic partition allocation technique called the "best-fit allocation method" assigns the smallest partition that is large enough for a process. This approach seeks out the division whose size is closest to that of the process. As it allocates the lowest division feasible, this approach is more effective than the first-fit allocation method.

The best-fit allocation approach has the benefit of minimizing memory waste. In order to guarantee that there is less unused memory, it allocates the smallest partition that is large enough for a process. The fact that this technique takes additional processing overheads to find the shortest split is one of its drawbacks.

Worst-fit Allocation Method

A form of dynamic partition allocation approach called worst-fit allocates the biggest available partition. The biggest partition that is accessible to a process is allocated using this strategy, which is the reverse of the best-fit allocation method. Because it might result in a substantial amount of memory waste, this strategy is not particularly effective.

The fact that bigger processes have access to the necessary quantity of memory is one of the benefits of the worst-fit allocation approach. Nevertheless, one drawback of this approach is that bigger partitions could not be completely exploited, which might result in substantial memory waste.

First Fit Allocation Method

A form of dynamic partition allocation approach called first fit allocation allocates the first available partition that is big enough for a process. The quickest and easiest way of dynamic partition allocation is this one. It looks for the first memory partition that is large enough to fit a process.

The fact that the first fit allocation approach is quick and effective is one of its benefits. Finding the first accessible partition does not need a lot of computing work. The risk of memory fragmentation is one of this method's drawbacks, too. The amount of memory left over after a process uses its partition might not be enough to support another process.

Comparison of Partition Allocation Methods

Partition Allocation Method



Fixed Partition

Simple, easy to use, no complex algorithms needed

Memory waste, inefficient use of memory resources

Dynamic Partition

Flexible, more efficient, partitions allocated as required

Requires complex algorithms for memory allocation

Best-fit Allocation

Minimizes memory waste, allocates smallest suitable partition

More computational overhead to find smallest split

Worst-fit Allocation

Ensures larger processes have sufficient memory

May result in substantial memory waste

First-fit Allocation

Quick, efficient, less computational work

Risk of memory fragmentation


An important component of memory management in operating systems is partition allocation techniques. The operating system can use them to effectively allot memory to processes as needed. The operating system's unique needs and the type of processes that run on it will determine the partition allocation mechanism that is used. Every partition allocation technique has benefits and drawbacks of its own, and the operating system designer must carefully take them into account when choosing a technique for their system. Computer experts must be familiar with the various partition allocation techniques in order to build and execute memory management systems that are effective, dependable, and tailored to the needs of each individual use case.

Updated on: 20-Jul-2023


Kickstart Your Career

Get certified by completing the course

Get Started