Memory pool management system capable of using memory efficiently

A searching order control portion 101 has a searching order table (FIG.3) for a memory pool having sub-memory pools (FIG.2). The searching order table has entries in which request memory area size ranges and corresponding searching orders are entered. The searching order control portion 101 finds the sub-memory pool that should be searched for an assignable memory area by the use of the searching order table in response to a request of a getting request receiving portion 102. The searching order control portion 101 notifies a sub-memory pool ID of the found sub-memory pool to the getting request receiving portion 102. The getting request receiving portion 102 makes a getting portion 104 try getting a memory area with request memory area size from the sub-memory pool of the sub-memory pool ID. The getting request receiving portion 102 repeats the above-mentioned operation until the getting portion 104 gets the memory area or the searching order control portion 101 notifies the end of search.