JPH0355643A - Memory pool control system with priority - Google Patents

Abstract

PURPOSE:To decrease the cases where the security is impossible for the tasks of high priorities by limiting the tasks that can secure the memories from a memory pool including the priority and assigning the memories with preference to the tasks having high priorities. CONSTITUTION:When the memories are secured from a certain idle memory in addition to a pool in a system, the memories are searched out of the pool control information 20 in the order of lower priorities via a memory search means 13 to a memory security task 40 of a specific priority that has the short of memories. Then the information 20 having the priority lower than that of the task 40 is selected, and the memories are secured out of the corresponding memory pool. Thus it is possible to decrease the memory security unable cases at request of memories based on the pool priority 21 without causing such a case where the memories stored in a relevant pool are used by the tasks of lower priorities.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a prioritized memory pool management method, and in particular, in a memory management method in an operating system, a priority is given to each fixed amount of memory, This paper relates to a prioritized memory pool management method that makes it possible to limit the tasks that can use the memory. [Prior art] In conventional memory management systems, memory allocation methods do not have the concept of pools for storing free memory, or even if there is a concept of pools, memory allocation from each pool is difficult regardless of the priority of the task. Because this was allowed, there was no way to prevent low-priority tasks from allocating large amounts of memory, and even when high-priority tasks tried to allocate memory, they were unable to allocate memory and could not operate. [Problems to be Solved by the Invention] In the conventional method described above, memory is allowed to be secured regardless of the priority of the task, so even high-priority tasks cannot secure memory due to large amounts of memory being secured by low-priority tasks. To avoid this, the memory is divided and managed as a pool, and if it is used only for arbitrary tasks, the disadvantage is that the memory is secured with a certain margin, resulting in a large amount of division loss. be.

[Means to solve the problem]

In order to solve the above problems, the prioritized memory pool management method of the present invention is a memory management method that stores an arbitrary amount of memory from free memory in the system as a pool, and stores memory that holds pool management information. a pool creation means; a memory pool priority setting means for adding a minimum priority to a task that is permitted to allocate memory from the memory pool; In this case, it is configured with a memory search means that searches for a memory pool with a lower priority than the priority of the source task and allocates memory from that pool. [Example] First, the structure of the present invention will be explained with reference to the drawings. FIG. 1 is a block diagram showing the structure of an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing an actual processing example of the present invention.

The present invention includes a prioritized memory pool management method 10 and a pool priority 21, and includes pool management information 20 for managing information about the created memory pool, a pool management information queue 30, and a memory reservation task 40. has been done.

Furthermore, the prioritized memory pool management method 10 extracts an arbitrary amount of free memory in the system and stores it as a memory pool, and uses the pool management information 20 as management information to queue it in the pool management information queue 30 in order of priority. a memory boolean creation means 11; and a memory boolean priority setting means 12 for setting the lowest priority that allows the use of the memory pool created by the memory pool creation means 11 as a pool priority 21 in the pool management information 20 for each memory pool. , If there is a shortage of free memory in the system other than the pool when memory is allocated from the memory allocation task J40, a memory pool with a lower priority than the memory allocation task 40 is searched for according to the system pool management information 20. It consists of a memory search means 13 that secures memory from memory stored in a pool. FIGS. 2(a) to 2(C) are explanatory diagrams showing specific examples of processing according to the present invention. This is an example. Note that the priority in the diagram indicates that the smaller the value, the higher the priority. Figure 2 (a) shows the state of the pool management information 20 in which three memory pools with different pool priorities 21 have been created, and in this state, memory is secured from free memory other than the pools in the system. In response to the memory reservation task 40 with priority 4 that encounters a memory shortage, the memory search means 13 selects the memory reservation task 40 with priority 4 from the pool management information 20.
Search for pool management information 20 with a lower priority than . Figure 2 (If a>, the pool management information 20 with pool priority 21 of 7 is selected and memory is secured from that memory pool. If the memory boolean with pool priority 21 is 7 is full searches for the pool management information 20 with the next lowest priority, but does not secure it from the memory pool with the pool priority 21 higher than the priority of the memory reservation task 40.The search range of the pool management information 20 at this time is shown below. Fig. 2(b) shows the search range of the pool management information 20 when the memory allocation task 30 with the highest priority O allocates memory and encounters a memory shortage. This is shown in Figure 2 (C). As described above, pool priority 21 prevents the memory stored in the pool from being taken from unexpected low-priority tasks, reducing cases where memory cannot be secured when requesting memory. [Effect of activation] As explained above, the present invention stores memory as a prioritized memory pool, limits the tasks that can allocate memory from that pool by task priority, and reduces the allocation of memory to high-priority tasks. By enabling preferential memory allocation, it is possible to reduce cases where high-priority tasks cannot allocate memory due to large amounts of memory allocated to low-priority tasks.

[Brief explanation of drawings]

Claims (1)

[Claims] The memory management method includes a memory pool creation means that stores an arbitrary amount of memory from free memory in the system as a pool and holds management information of the pool, and a minimum priority of a task that is allowed to secure memory from the memory pool. Added memory pool priority setting means, and if memory cannot be secured due to insufficient memory when securing memory from free memory in the system other than the above pool, searches for a memory pool with a lower priority than the priority of the securing source task and uses that pool. A memory pool management method with priority, comprising a memory search means for securing memory.