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1. Valgrind Still Reachable
2. Valgrind Solaris

Overview

The Linux Tools Project Valgrind plugin aims to provide simple and effective profiling for the C/C++ Development Tools. There is an abundance of Valgrind functionality to expose in Eclipse. Valgrind itself is very component based and this relates well to Eclipse plugins. The main architectural goal is to have a common Valgrind user interface and underlying launch framework, while the Valgrind tools themselves are contributed via extension points. As with most tools in this project, the aim is to provide not just a user interface for the underlying tool. Instead, this project will attempt to exploit every opportunity to integrate into the Eclipse workbench to provide a unique and formidable user experience.

Valgrindis a memory mismanagement detector. It shows you memory leaks, deallocation errors, etc. Actually, Valgrind is a wrapper around a collection of tools that do many other things (e.g., cache profiling); however, here. May 11, 2019 Valgrind 原理 valgrind 是一个提供了一些 debug 和优化的工具的工具箱，可以使得你的程序减少内存泄漏或者错误访问. Valgrind 默认使用 memcheck 去检查内存问题.

Extensibility

• Each tool has the ability to contribute its own set of options to the Launch Configuration Dialog via the valgrindTools extension point and providing an implementation of the IValgrindToolPage interface. The controls created inside of the implementing class are nested into a tool specific tab in the Dialog.
• An extender must also implement the IValgrindLaunchDelegate interface. This will control the lifecycle of the contributed tool and will receive control to parse the output of the underlying Valgrind process once the main delegate is finished.
• There is a single Valgrind View, which by itself contains no output. Each tool provides its own appropriate way of displaying its output and, similar to the Launch Configuration Dialog, can embed its contributed controls into the View. This is done via the valgrindToolViews extension point and implementing the IValgrindToolView interface.

Memcheck

Memcheck is a tool that detects memory management problems. It is Valgrind's most popular tool and seemingly the most mature. Memcheck's output is rather straight forward - it is a series of errors along with stack trace information.

• The Valgrind View presents this output using a TreeViewer with the errors as top-level elements.
• The stack trace is presented underneath the error and when a frame is double-clicked an editor will open and go to the line in question.
• Markers represent memcheck errors inside the editor and are linked to the Problems View.
• Includes an editor for Valgrind suppressions files featuring syntax highlighting, folding and code completion.

Massif

Massif is a heap profiling tool. It takes several 'snapshots' during execution of your program detailing the various heap allocations throughout. It's output for each snapshot primarily consists the time of the snapshot, how many bytes were allocated that can be used, and how much extra was allocated than was asked. The unit of time can be configured to be instructions, milliseconds or bytes. At specified intervals, 'detailed' snapshots are produced. These detailed snapshots contain a tree of heap allocations that comprise that snapshot. Unlike Memcheck, Massif does not yet support XML output. Massif's output is complex and as such requires creative ways of displaying it. Valgrind includes the ms_print program that is used to display Massif's output in a visually appealing manner. ms_print was used as a template for how to display this output.

• The default view of the output is with a TableViewer. Snapshots are displayed as tabular data, just as ms_print does.
• For detailed snapshots, an icon indicates the snapshot can be double-clicked and the View will display a TreeViewer of the detailed snapshots' heap allocation trees.
• ms_print also provides a bar chart of bytes allocated throughout execution. In perhaps a more appropriate style, there is an option to display a detailed line chart of this data.

Cachegrind

Cachegrind performs cache and branching profiling. A Cachegrind profile run measures the number of cache misses and branch mispredictions performed by an application. The results of a Cachegrind profile run are displayed in the Valgrind view. These results show Cachegrind's cache/branch data in different levels of granularity.

• Double-clicking on any file, function, or line will open the corresponding source file and place the cursor on the appropriate location (if the source can be resolved).
• Integration with the CDT's parsed code model provides a user interface that resembles what you see in the Outline view.

Future Plans

• Caching output from recent Valgrind runs for quick restoration
• Integration of the remainder of the Valgrind tool suite

Try it out

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Check out the source code from our Git repository

Welcome friends. In this Linux tutorial, we’ll teach you about a special technique known as code profiling and discuss Valgrind which is the best-known code profiling tool available on Linux platforms.

Code profiling helps you improve the space and time complexity of a program. It lets you isolate the bottlenecks in your code.

As you know, in C/C++ programming world, performance is the key element to classify these languages from other high-level languages. C/C++ developers remain busy in tuning their code to run faster.

But you can’t always rely on human skills to optimize your program for performance. So it’s inevitable to use code profiling tools like Valgrind. Let’s learn it today.

Code profiling tools allow dynamic analysis of code. They not only support run-time analysis but also work as a leak checker. You can use them to find memory leakage in your source code.

Before we go into the details of Valgrind, let’s first understand the concept of code profiling and leak-checker in detail.

What is code profiling?

Code profiling is an essential facet of programming. Some of you may already know about code profiling yet few of us could wonder what it is. Code profiling is the process to determine which part of the program is depleting resources. And it can expose the program sections which are consuming time within the application.

For example, say your program spends half of the time in string-handling routines. And there is a possibility to stimulate these functions by 10 percent. It means the overall application’s execution time will improve by 5 percent.

In the next sections, we’ll discuss Valgrind commands and some useful tips-tricks for code profiling and leak detection.

What is Valgrind?

It is an open source framework, popular code profiling, and leak checker tool. You can instantly use it to detect dynamic memory and threading bugs, and profile application in detail. Alternatively, you can utilize it to develop new tools.

So this tool offers much more than just code profiling and finding leaks.

How to install Valgrind?

You can install it using the Package manager for your OS, but we’ll guide you to build it from the source code. It will help when you run and debug your program on multiple OS.

Follow the steps given below to download and build source code.

Valgrind installation steps.

• Pull Valgrind source archive file to get the source.
• Unpack the archive to extract the files onto your system.
• Run “./configure” command to prepare build configurations.
• Use the make command to start the build, just like you use to do.
• Run <sudo make install> to install it onto your system.

Alternatively, you can use the below automated script to build and install Valgrind.

Shell Script for Installing Valgrind.

Valgrind Command Syntax and Options.

Once you successfully make theValgrind, you can explore the various commands and options it brings to the plate. Here we are presenting most needed and useful one for you.

Syntax.

Commands and Options.

Don’t presume that we are now closer to the end of the article. There is still one more crucial concept which we want to touch upon in the next section.

What is Suppression and why it is needed?

So far we’ve seen a lot of code profiling and leak checker stuff. Now the turn is to suppress errors that you don’t want to see. These are the leaks outside of your code i.e. in shared libraries and are false positive.

Suppression Example.

For example, the code profiling tool detects many issues in the system libraries, such as the C library, which come pre-installed with your OS.

You can’t fix these defects, but you can hide these errors. So Valgrind brings the concept of suppression to hide such errors which are outside of your purview, or you do not want to see.

Steps for suppression.

1. Run your program using the following command.

This command produces the suppression code for each and every error it finds in your program.

Valgrind Still Reachable

2. Now locate the system library errors that we are not going to fix. Copy suppression code for those errors in a separate file.

3. Next, save the above file with .supp extension.

4. Again run your program with the following command.

5. This time, Valgrind will ignore all the errors which are in the suppression file. And you will only see the suppressed error count instead of the defects in the end.

Valgrind Solaris

Summary – Valgrind as a Profiling and Leak Checker Tool.

We wish that there is something new for you to learn from the above extract about Valgrind. And you could apply this knowledge in your production environment.

Our team is already benefiting from this fantastic code profiling tool, and this article is the crux of their real-time experience with it. In the end, we request you to share this post with your friends and on the social media of your choice.

Keep Optimizing,

TechBeamers.