Difference between Memory Pooling and Dynamic Allocation in C++

In this article, we will discuss the differences between Memory Pooling and Dynamic Allocation in C++. Before discussing their differences, we must know about Memory Pooling and Dynamic Allocation with their features and use cases.

What is the Memory Pooling?

Memory pooling is an optimization mechanism aimed at minimizing the resource expense incurred by allocating and deallocating memory by allocating a fixed amount of memory at one time. Instead of programs approaching, the heap to get memory for each allocation, programs make do with the pool. Therefore, it cuts the overhead of frequently getting memory from the heap as well as solves problems with fragmentation.

This approach is especially valuable in applications that depend greatly on performance or in systems with Pause/Transient working set characteristics because it speeds up the allocation rate and achieves better locality of reference. Despite this, memory pooling is not as flexible as dynamic allocation because it is normally used when a block size needs to be defined and it is very useful when used with objects of a fixed size only.

Features of Memory Pooling:

Several key features of Memory Pooling are as follows:

1. Improved Performance: Memory pooling is advantageous because it provides blocks of pre-allocated memory, thereby minimizing the time, which is spent on allocation and deallocation.
2. Reduced Fragmentation: This is because memory blocks are used repeatedly and hence leads to reduction of heap fragmentation, boosting memory locality, and usage speeds.
3. Fixed-size Blocks: Pools are typically applicable with fixed-size objects or data, thus leading to efficient allocations and deallocations.
4. Limited Flexibility: Memory pools compared to dynamic allocation are relatively inflexible because the memory pools are normally established by size boundaries or by object type.

Use Cases:

Several use cases of Memory Pooling are as follows:

Embedded Systems:

• It is most useful in situations where the amount of memory is an issue and when fixed-size objects are utilized frequently.

Real-time Systems:

• It is suitable for applications that need to produce deterministic results and cannot spend much time and space resources on allocation.

High-performance Applications:

• It has been beneficial for systems that have some performance-critical parts of the code that need a lot of memory allocation/deallocation, such as, networking servers or game engines.

What is the Dynamic Memory Allocation?

Dynamic memory allocation in C++ means the allocation of memory at the time of execution of the program using a new operator. This makes it possible for developers to allocate memory from the heap so that we can create flexible structures of data whose size can change depending on the demands of the running program. Even though dynamic allocation offers a lot of flexibility and is best suited for a case where the size of the data cannot be predicted at the time of compilation. It has a drawback that includes slack in terms of performance and memory fragmentation, which is also required to be managed efficiently to avoid memory leaks and inefficiency.

Features of Dynamic Memory Allocation:

Several key features of Dynamic Memory Allocation are as follows:

1. Manual Management: This makes it mandatory for the developer to allocate memory using the new keyword for the creation of new objects, and delete as the keyword for freeing space.
2. Variable Size: It can allocate memory that is just enough for data at a particular time, which is suitable when the size of data is not known as the time of compiling the program.
3. Potential Fragmentation: Due to the dynamic manner of creating and deleting memory, heaps could grow fragmented with increasing amount of allocation time.

Use Cases:

Several use cases of Dynamic Memory Allocation are as follows:

Dynamic Data Structures:

• Application for constructing data structures like linked lists, trees, or graphs where sizes are frequently or variably in transit.

Applications with Variable Data Requirements:

• It is appropriate for programs where the size of data is unpredictable at the time of development of the program, such as, DBMS or graphical applications.

General-purpose Programs:

• A class of programs that do not have a required amount of memory at compile time and require memory during the run time of the program.

Key differences between Memory Pooling and Dynamic Allocation:

There are several differences between Memory Pooling and Dynamic Allocation in C++. Some main differences are as follows:

Conclusion:

In conclusion, Dynamic allocation and memory pooling are useful basic models in C++ memory management, where dynamic allocation gives flexibility and memory pooling gives effectiveness and velocity. The choice of one over the other depends on the need of the application whether it calls for performance optimization or flexibility.