A memory debugger is a

debugger A debugger is a computer program used to test and debug other programs (the "target" programs). Common features of debuggers include the ability to run or halt the target program using breakpoints, step through code line by line, and display ...

for finding software memory problems such as

memory leak In computer science, a memory leak is a type of resource leak that occurs when a computer program incorrectly manages memory allocations in a way that memory which is no longer needed is not released. A memory leak may also happen when an objec ...

s and buffer overflows. These are due to bugs related to the allocation and deallocation of dynamic memory. Programs written in languages that have garbage collection, such as

managed code Managed code is computer program code that requires and will execute only under the management of a Common Language Infrastructure (CLI); Virtual Execution System (VES); virtual machine, e.g. .NET, CoreFX, or .NET Framework; Common Language R ...

, might also need memory debuggers, e.g. for memory leaks due to "living" references in collections.

Overview

Memory debuggers work by monitoring memory access, allocations, and deallocation of memory. Many memory debuggers require applications to be recompiled with special dynamic memory allocation libraries, whose APIs are mostly compatible with conventional dynamic memory allocation libraries, or else use dynamic linking.

Electric Fence An electric fence is a barrier that uses electric shocks to deter humans and other animals from crossing a boundary. Most electric fences are used for agricultural purposes and other non-human animal control. They may also be used to protect hig ...

is such a debugger which debugs memory allocation with

malloc C dynamic memory allocation refers to performing manual memory management for dynamic memory allocation in the C programming language via a group of functions in the C standard library, namely , , , and . The C++ programming language includ ...

. Some memory debuggers (e.g. Valgrind) work by running the executable in a virtual machine-like environment, monitoring memory access, allocation and deallocation so that no recompilation with special memory allocation libraries is required. Finding memory issues such as leaks can be extremely time-consuming as they may not manifest themselves except under certain conditions. Using a tool to detect memory misuse makes the process much faster and easier. As abnormally high memory utilization can be a contributing factor in

software aging In software engineering, software aging is the tendency for software to Software failure, fail or cause a system failure after running continuously for a certain time, or because of ongoing changes in systems surrounding the software. Software a ...

, memory debuggers can help programmers to avoid software anomalies that would exhaust the computer system memory, thus ensuring high reliability of the software even for long runtimes.

Comparison to static analyzer

Some static analysis tools can also help find memory errors. Memory debuggers operate as part of an application while its

running Running is a method of terrestrial locomotion by which humans and other animals move quickly on foot. Running is a gait with an aerial phase in which all feet are above the ground (though there are exceptions). This is in contrast to walkin ...

while

static code analysis In computer science, static program analysis (also known as static analysis or static simulation) is the analysis of computer programs performed without executing them, in contrast with dynamic program analysis, which is performed on programs duri ...

is performed by analyzing the code without executing it. These different techniques will typically find different instances of problems, and using them both together yields the best result.

List of memory debugging tools

This is a list of

tools A tool is an object that can extend an individual's ability to modify features of the surrounding environment or help them accomplish a particular task. Although many animals use simple tools, only human beings, whose use of stone tools dates ...

useful for memory debugging. A profiler can be used in conjunction with a memory debugger.

References

*Michael C. Daconta: C++ Pointers and Dynamic Memory Management, John Wiley & Sons, * Andrew Koenig: C Traps and Pitfalls, Addison-Wesley,

External links

Hunting Memory Bugs
by Ivan Skytte Jørgensen

by Jean-Philippe Martin {{Memory management navbox Memory management software Debugging

Overview

Comparison to static analyzer

List of memory debugging tools

See also

References

External links