A memory pool is a block of memory assigned to a specific program or application on the computer. Information for a running program, such as the operating system or any open application on the computer, is stored in Random Access Memory (RAM) on a computer. Assigning each program a specific block of memory using memory pool technology avoids the problem of memory overlap. Overlap occurs when two programs are trying to use the same sections of memory; like attempting to share a slice of pie, the programs can end up "fighting" over the shared memory, resulting in errors on the system. With a memory pool, each program is given its own "slice," resulting in harmonious operation of the computer.
A user can think of the RAM in the computer like a simple multi-storied bookshelf. Without memory pool usage, as information comes in, the computer will just start filling the shelves from top to bottom indiscriminately, splicing information so that no linear logical structure exists within the memory. While this is a completely valid approach to handling memory, trading organization for speed, the downside comes when programs are removed from memory and new programs take their place. Chances are good that the information needed by the new program will not fit snugly into the gaps freed up as the old program was removed. Without memory pooling, this discrepancy forces the computer to further compromise organization within the RAM; this is known as fragmentation.
Having fragmented information in memory means that the computer will have to perform a juggling act to retrieve information for any specific program. With memory pooling, fragmentation is minimized as the computer assigns each program a specific area within the "bookshelf" of memory, minimizing the risk of disorganization. This results in a bit of extra overhead on the computer at the outset, as it has to perform its memory "juggling" when the program is first loaded, but substantially increases efficiency of the program while it is running, as the computer will already know where to look on the "shelf" for the program's information.
The operating system generally controls the operation of the memory pool. It has the ability to allocate, distribute, and rearrange the different "pools" within the computer's RAM, adjusting as necessary to the demands of individual applications. For example, if an application requests a larger block of memory than it has been assigned, the operating system must act to enlarge the specific pool assigned to that program without encroaching on the memory pools of any other active programs on the system. Optimizing this requires that a particular application be tuned for a particular operating system and vice versa, ensuring that both work together to allocate and reserve memory for the application in the most efficient possible manner.