Garbage collecting method based on Java system on chip (SoC) with stack system structure

Abstract

The invention discloses a garbage collecting method based on a Java system on chip (SoC) with a stack system structure, which is used for a multi-thread dynamic scheduling garbage collector and used for recovering garbage. The life cycle of the Java SoC is divided into a system initialization stage and a real-time task stage, wherein at the Java SoC initialization stage, a Java virtual machine actively calls the garbage collector to carry out single-thread explicit called garbage collection; when an abnormity of 'memory insufficiency' happens, the Java SoC triggers and calls the garbage collector to carry out single-thread explicit called garbage collection; and at the multi-thread real-time task operation stage, a concurrent collector thread schedules the garbage collector to collect garbage in a cycle TC. The garbage collection workflow of the garbage collector comprises the following steps of: 1) scanning root set objects in the Java SoC; 2) marking; 3) copying non-garbage objects from a subspace fromespace to a subspace tospace; 4) sweeping handles; 5) emptying the subspace fromespace; and 6) turning the subspaces fromespace and tospace over.

Description

technical field [0001] The present invention designs a JavaSoC garbage collection method, specifically, designs a garbage collection method for a JavaSoC system based on a stack architecture for garbage collection by a multi-thread dynamic scheduling garbage collector. Background technique [0002] In recent years, Java technology has been widely used in embedded systems by virtue of its unique cross-platform, good packaging and security. At the same time, with the rapid development of ultra-high integration chip technology and technology, it becomes possible to implement JVM (Java Virtual Machine) with hardware, and Java processors emerge as the times require. JavaSoC integrates modules such as the Java processor core, system bus, and peripheral controller into a small chip, which not only significantly improves the running speed and processing capacity of Java programs, but also integrates rich peripheral interfaces. Design, especially embedded Java computing and applicat...

AI Technical Summary

Problems solved by technology

The GC of the mainstream PC platform has relatively high requirements on system resources, and its running status is generally unpredictable, so it is not suitable for embedded and real-time environments. On the contrary, such systems generally do not have garbage collection functions.

[0004] Chinese patent application number 200710026998.2 discloses a Java Card garbage collection method in the patent application "Java Card System Garbage Collection Method", which uses a single thread to explicitly call garbage collection, that is, stops all (Stop-The-World, STW for short) The way of working is to stop the execution of other applications when the garbage collection starts. This method can realize garbage collection, but for the application in the field of embedded real-time environment, on the one hand, it is impossible to predict the time required for garbage collection; Enough available memory has been reclaimed during the execution of the application program, so it cannot meet the high real-time requirements of the embedded field

Images