So my company uses a delightfully buggy program called Rational Purify (as a plugin to Microsoft Visual Developer Studio) to manage memory leaks. The program is deigned to let you click on a memory leak after you have encountered it, and then jump to the line that the leak occurs on. Unfortunately Purify is malfunctioning and Purify wi...
Say we have the following method: private MyObject foo = new MyObject(); // and later in the class public void PotentialMemoryLeaker(){ int firedCount = 0; foo.AnEvent += (o,e) => { firedCount++;Console.Write(firedCount);}; foo.MethodThatFiresAnEvent(); } If the class with this method is instantiated and the PotentialMemoryLea...
I have a huge web app that is having issues with memory leak in IE 6. Fixing a memory leak in a 5 line code sample that demonstrates the problem is easy. But if I have a very huge application, where should a start from? ...
What are all the possible ways in which we can get memory leaks in .NET? I know of two: Not properly un-registering Event Handlers/Delegates. Not disposing dynamic child controls in Windows Forms: Example: // Causes Leaks Label label = new Label(); this.Controls.Add(label); this.Controls.Remove(label); // Correct Code La...
I have a .exe and many plug-in .dll modules that the .exe loads. (I have source for both.) A cross-platform (with source) solution would be ideal, but the platform can be narrowed to WinXP and Visual Studio (7.1/2003 in my case). The built-in VS leak detector only gives the line where new/malloc was called from, but I have a wrapper for...
In one of my VB6 forms, I create several other Form objects and store them in member variables. Private m_frm1 as MyForm Private m_frm2 as MyForm // Later... Set m_frm1 = New MyForm Set m_frm2 = New MyForm I notice that I'm leaking memory whenever this (parent) form is created and destroyed. Is it necessary for me to assign these me...
Essentially I want to know if in VB.NET 2005 if using a sqlcommand and then reusing it by using the NEW is wrong. Will it cause a memory leak. EG: try dim mySQL as new sqlcommand(sSQL, cnInput) // do a sql execute and read the data mySQL = new sqlcommand(sSQLdifferent, cnInput) // do sql execute and read the data catch ... final...
We've been using "Drip" to try and identify why pages with UpdatePanels in them tend to use a lot of client-side memory. With a page with a regular postback, we are seeing 0 leaks detected by Drip. However, when we add an update panel to the mix, every single DOM object that is inside of the update panel appears to leak (according to D...
In unmanaged C/C++ code, what are the best practices to detect memory leaks? And coding guidelines to avoid? (As if it's that simple ;) We have used a bit of a silly way in the past: having a counter increment for every memory allocation call and decrement while freeing. At the end of the program, the counter value should be zero. I kn...
What memory leak detectors have people had a good experience with? Here is a summary of the answers so far: Valgrind - Instrumentation framework for building dynamic analysis tools. Electric Fence - A tool that works with GDB Splint - Annotation-Assisted Lightweight Static Checking Glow Code - This is a complete real-time performanc...
Does anybody know a "technique" to discover memory leaks caused by smart pointers? I am currently working on a large project written in C++ that heavily uses smart pointers with reference counting. Obviously we have some memory leaks caused by smart pointers, that are still referenced somewhere in the code, so that their memory does not ...
I use fdopen to associate a stream with an open file. When I close() the file, is the stream automatically disassociated as well, and all stream memory returned to the OS, or do I need to be aware of the fdopen'd file and close it in a specific manner? ...
I have been working on some legacy C++ code that uses variable length structures (TAPI), where the structure size will depend on variable length strings. The structures are allocated by casting array new thus: STRUCT* pStruct = (STRUCT*)new BYTE [sizeof(STRUCT) + nPaddingSize]; Later on however the memory is freed using a delete call:...
I develop an extension module for Guile, written in C. This extension module embeds a Python interpreter. Since this extension module invokes the Python interpreter, I need to verify that it properly manages the memory occupied by Python objects. I found that the Python interpreter is well-behaved in its own memory handling, so that...
Recently I ran into this error in my web application: java.lang.OutOfMemoryError: PermGen space It's a typical Hibernate/JPA + IceFaces/JSF application running on Tomcat 6 and JDK 1.6. Apparently this can occur after redeploying an application a few times. ...
I would like to repeatedly capture snippets of audio on a Nokia mobile phone with a Java Midlet. My current experience is that using the code in Sun's documentation (see: http://java.sun.com/javame/reference/apis/jsr135/javax/microedition/media/control/RecordControl.html) and wrapping this in a "while(true)" loop works, but the applicati...
(Jeopardy-style question, I wish the answer had been online when I had this issue) Using Java 1.4, I have a method that I want to run as a thread some of the time, but not at others. So I declared it as a subclass of Thread, then either called start() or run() depending on what I needed. But I found that my program would leak memory ov...
I'm working on a large application (300K LOC) that is causing a memory leak in the Sun 1.6 JVM (1.6_05). Profiling the Java shows no leak. Are there any diagnostics available from the JVM that might detect the cause of the leak? I haven't been able to create a simple, isolated Java test case. Is the only way to figure this out by using a...
I had recently a problem with oom-killer starting to kill processes after some time. I could see that the memory was consumed, but by the time I got to the server it wasn't clear anymore what consumed it. Is there a good non-obvious place to get more info about oom-killer? E.g. detailed info about processes at the time of activation, det...
I have been having some issues with LINQ-To-SQL around memory usage. I'm using it in a Windows Service to do some processing, and I'm looping through a large amount of data that I'm pulling back from the context. Yes - I know I could do this with a stored procedure but there are reasons why that would be a less than ideal solution. An...