Are your applications running slow? Perhaps they aren’t behaving correctly, or are unexpectedly crashing?
There are a number of causes for performance issues in applications, and these issues can be found and solved using a process called debugging.
What Is Debugging?
Debugging is the process of analyzing how your program runs, how it generates data in order to find defects and issues in your code. These errors or defects are referred to as “bugs”, hence the term “debugging.”
Debugging is not always about finding problems in the code. It can also be used to simplelearn how code runs so a developer gains a thorough understanding of it before they refactor or enhance the code with new functionality. This form of debugging is typically called dynamic analysis.
A debugger is a fantastic tool for either of these cases.
What Does a Debugger Do?
A debugger is a tool that is typically used to allow the user to view the execution state and data of another application as it is running. Debuggers allow users to halt the execution of the program, examine the values of variables, step execution of the program line by line, and set breakpoints on lines or specific functions that, when hit, will halt execution of the program at that spot. In this view, seeing how the program is viewed by their computer, the user can discover how a program flows, identify incorrect code and data, and find semantic errors in the program.
How to Debug a Program
There are a number of different techniques or ways you can go about debugging an application.
Interactive Debugging
The most common debugging technique is interactive debugging. In this process, you’ve loaded your program with the debuggers graphical user interface (GUI) and analyze the running program by stepping through code, setting break points, examining program data, and looking at how it's running.
Reverse Debugging
Advanced debuggers allow users to record the execution of the program and allow users to perform all the usual operations for stepping code in reverse. This time-saving technology allows developers to quickly hone in on errors in one debugging session. Reverse debugging is also a fantastic tool for performing dynamic analysis and gaining a thorough understanding of how a program runs.
Remote Debugging
Interactive debugging is often coupled with remote debugging. With remote debugging, you are debugging an application that is deployed on a different computer from a remote location. This could be anywhere — the other side of the lab, the other side of your campus, or even across the country or world. A debugger needs the capabilities to be able to debug remotely on that type of system.
Post-Mortem Debugging
Post-mortem debugging is a technique where you've gathered information during a run, but you don't have access to it until later, and then your programming crashes. In this scenario, you want to gather as much information as you can so it can be analyzed later to diagnose what happened during the run of your program.
Delta Debugging
Also called comparative debugging, this is a way of comparing one run to another, or two programs running side-by-side and looking for ways that they differ in their execution of the lines that they're going through, or the ways that their data differs between the two.
Batch Debugging
This may also be referred to as unintended debugging. In this scenario, the debugger is still in control of your program even while you're not sitting in front of a GUI. The debugger is driving the program through to completion and along the way it will save that off, so that a post-mortem debugging can be performed later.
TotalView Debugging Tools
Perforce’s debugger, TotalView, provides all of the features and more discussed in this article. It also supports all of the debugging techniques listed earlier, providing all the tools required by developers to efficiently debug and dynamically analyze their complex applications.
See how debugging a program is easier and faster with TotalView by signing up for a free trial.
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By using the TotalView HPC debugger, developers can save time and boost the performance and scale of their HPC applications by taking advantage of: The most advanced GPUs, CPUs, and memory technologies. Resources across clusters. Tools for working on remote clusters in real time.
What is the purpose of a debugger? ›
When software does not work as expected, computer programmers study the code to determine why any errors occurred. They use debugging tools to run the software in a controlled environment, check the code step by step, and analyze and fix the issue.
What is the function performed by a debugger? ›
A debugger is a software tool that can help the software development process by identifying coding errors at various stages of the operating system or application development. Some debuggers will analyze a test run to see what lines of code were not executed.
What are the roles and responsibilities of debugger? ›
Debuggers also offer more sophisticated functions such as running a program step by step (single-stepping or program animation), stopping (breaking) (pausing the program to examine the current state) at some event or specified instruction by means of a breakpoint, and tracking the values of variables.
What things does a debugger allow you to do? ›
Key things that you can use the debugger to determine are:
- The flow of the program (what happens next on a line by line basis)
- The creation of variables.
- The data being stored in each variable.
- The entering/leaving of functions.
- The calculations that are made.
- The entering of IF statements or ELSE statements.
Advantages of Debugging
- It helps in delivering high-quality applications by identifying and resolving bugs.
- It helps to increase the application's stability and reliability.
- If we fix the bugs in the early stage, we can save a lot of money.
- It helps developers to understand the codebase clearly.
A debugger enables the programmer to step through code in execution, place breakpoints in the code, view memory, change variables, and track variables, among other capabilities.
What is the primary goal of debugging? ›
The purpose of debugging is to fix those defects or errors. It is the process to identify the failure of implemented code. It is the process to give absolution to code failure. Debugging typically involves using tools and techniques such as logging, tracing, and code inspection.
Why is debugging so difficult? ›
What makes debugging so difficult? It's no secret that fixing bugs is difficult when learning to program. This is completely understandable; learners have to understand program concepts, sequencing, syntax, and more when starting out, which is hard to keep track of.
What is the difference between debugging and testing? ›
Testing is conducted to verify a software system's functionality, performance, and reliability to identify defects or errors. Debugging is investigating and resolving those defects, aiming to eliminate issues and ensure smooth operation.
Debuggers
- Run the program.
- Define conditions under which the execution should stop and hand over control to the debugger. ...
- When the program stops, you can observe the current state, including. ...
- When the program stops, you can step through program execution, having it stop at the next instruction again.
Debugging means to run your code step by step in a debugging tool like Visual Studio, to find the exact point where you made a programming mistake. You then understand what corrections you need to make in your code and debugging tools often allow you to make temporary changes so you can continue running the program.
How do debuggers attach to a process? ›
When the debugger attaches to a running process, the process can contain one or more types of code. The code types the debugger can attach to are displayed and selected in the Select Code Type dialog box. Sometimes, the debugger can successfully attach to one code type, but not to another code type.
Why do I need a debugger? ›
A debugger allows you set conditional breakpoints, skip whole sections of code, evaluate code using the actual context that the application had when it was stopped, make changes to variables while the program is being executed, it is a great tool to explore code and behavior.
What are the three important points that should be considered while debugging? ›
The Linear Approach to Debugging
Trace the Code: Follow the code flow to identify where things might be going awry. Isolate the Issue: Narrow down to the specific section or line of code causing the problem. Implement a Fix: Modify the code to resolve the issue.
What makes a good debugger? ›
A good debugger can freeze and unfreeze threads. You can select which threads should execute and which should sleep. This makes debugging of heavily parallelized code much much easier and you can also emulate different race conditions and deadlocks.
What is the purpose of testing and debugging? ›
Testing is conducted to verify a software system's functionality, performance, and reliability to identify defects or errors. Debugging is investigating and resolving those defects, aiming to eliminate issues and ensure smooth operation.
What is the purpose of a debugger what happens when a breakpoint is set? ›
A breakpoint instructs the debugger to stop at a particular code location in the user's program, returning control of the debugger to them. The user may then inspect the application's state. Breakpoints are by far the most common type of debug event that developers use.
What is the function of debugging tool? ›
Debuggers are distinct tools that give developers the ability to watch and control how their program is being run. A debugger lets you set a breakpoint in your code, normally by highlighting a line of code, then when the application runs in debug mode the debugger can intercept the program and halt execution.
