Method for improving utilization rate of large pages of operating system

Abstract

The invention discloses a method for improving the utilization rate of large pages of an operating system. The method comprises the steps that (1) the system adds a variable a in a virtual address space data structure of each process, and each variable a is recorded as a heap top position of a distributed virtual address of the corresponding process; (2) in the process starting, the system initiates a to 0; when any process calls a heap top setting function for the application of an internal storage, a heap top parameter b is transmitted into the system; (3) the system calculates a value c after the alignment of upward large pages of the heap top positions according to a previously-requested heap top position and a currently-requested heap top position b of the process; (4) the system assigns the current value of a to a highest heap address variable of the recorded and distributed internal storage of the process, and compares the current value with c; if the current value is smaller than c, a stack space of the process is increased according to a difference value between the current value and c; if the current value is smaller than c, the release of the internal storage is implemented; if the current value is equal to c, the calling of the internal storage is not implemented. According to the method, the utilization rate of the large pages is fully improved, so that the performance of a program is improved.

Description

technical field [0001] The invention relates to a method for increasing the utilization rate of large pages of an operating system, and belongs to the technical field of operating system memory management. technical background [0002] Paging is a common feature of modern CPUs. It establishes a mapping from the program's virtual memory space to the machine's physical memory. Memory is managed in units of pages. Many CPU architectures, including Intel x86, implement a large page mechanism, which supports physical page granularities of different sizes such as 4k, 2M, and 4M. [0003] For the sake of simplicity, the current operating system (such as Linux) generally uses 4K pages, which makes the range of virtual addresses covered by each mapping only 4K. If a memory with a length of 2M needs to be accessed, the operating system needs to handle 512 page fault interrupts, and each page fault interrupt allocates 4K memory. [0004] Taking the Linux operating system as an exam...

AI Technical Summary

Problems solved by technology

The application of the virtual address of the application does not meet the requirements of large page alignment in many cases, which makes the Linux kernel not allocate large pages and use small pages instead

In this way, in many cases, the Linux kernel will not allocate large pages to programs, and the utilization rate of large pages is not high.

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