• Advertisement
Sign in to follow this  

OpenGL Posssible memory leak in OpenGL Intel Win7 drivers

This topic is 2166 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

int *ptr, MSVC 2008, debug build, value of 0x0018f668.

Just because it works on one person's machine using a specific compiler does not make it globally valid. The C/C++ standard is quite explicit that uniitalized pointers are undefined. That means that the compiler is largely free to do whatever it wants with them; it may give a value of 0, it may set to random garbage, and that random garbage may or may not point to somewhere valid in memory.

If you're in the habit of doing this, and of relying on it, please remind me to never use any software you write.

Share this post


Link to post
Share on other sites
Advertisement

If you're in the habit of doing this, and of relying on it, please remind me to never use any software you write.


I always clean up any warning the compiler gives, and this includes uninitialized variables. So that kind of thing isn't going to happen ever in software I write.

Share this post


Link to post
Share on other sites

But you define all your pointer variables global, not local?


why did you think that? I just wanted to show you a case where an uninitialized pointer actually is initialized. That was all.
I didn't imply that I use only global variables...

Share this post


Link to post
Share on other sites
why did you think that? I just wanted to show you a case where an uninitialized pointer actually is initialized. That was all.
I didn't imply that I use only global variables...

Previously you said, I'm quoting: "and pointer declaration depends on the compiler (but you are right it should be undefined)". But Now you say they are initialized...

How can "uninitialized pointer" be actually "initialized". There is no such thing as global unitialized variable from users point of view. C standard requires all global variables to be initialized to 0 or by calling C++ constructor.

Share this post


Link to post
Share on other sites

[quote name='mshafey' timestamp='1329247414' post='4913082']
Thanks for the suggestion. I've tried your code, it works, but it doesn't fix the leak. I'm still seeing memory leaking at the same rate on the affected platforms.

That's interesting. Let's try to pin down which call is causing it. What happens if you comment out the glTexSubImage2D call? And if you comment out the glMapBuffer block (but leave glTexSubImage2D in and coming from the PBO)?
[/quote]

gDEBugger with the code I posted in the first post. Upon application exit it says "Checking for memory leaks - Context 1 deleted. Memory Leak: 2 object(s) are leaked in GL Context 1 [Leak Size: 2,400KB]". Here are Process Explorer graphs for the original code running for a few minutes.

GPU graph: http://i.imgur.com/KgXix.png
Performance graph: http://i.imgur.com/bD9RH.png

I took out glMapBuffer()/glUnmapBuffer() block. Leak persists. Same for the glTexSubImage2D() call. Took them both out and still. Which lead me to remove everything except just basic calls to draw a rectangle switching colors. I'm sorry I sent everyone in the wrong direction here. It seems like even the most basic GL code causes Windows 7 machines to leak memory. I trimmed it down to this and it still leaks.



void paintGL();
void timerCallback(int value);
void changeSize(int w, int h);

unsigned char c = 255;

int main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
glutInitWindowPosition(300, 300);
glutInitWindowSize(640, 480);
int windowHandle = glutCreateWindow("Window");
glutDisplayFunc(paintGL);
glutReshapeFunc(changeSize);
timerCallback(0);
glutMainLoop();
glutDestroyWindow(windowHandle);
return 0;
}

void paintGL()
{
c = c? 0 : 255;
glColor3ub(c, c, c);
glBegin(GL_QUADS);
{
glVertex3f(-1, 1, 0);
glVertex3f(1, 1, 0);
glVertex3f(1, -1, 0);
glVertex3f(-1, -1, 0);
}
glEnd();

glutSwapBuffers();
}

void changeSize(int w, int h)
{
glViewport(0, 0, w, h);
}

void timerCallback(int value)
{
glutPostRedisplay();
glutTimerFunc(5, timerCallback, 0);
}



I might add that in some runs, this code starts off at about 18 MB and goes up to and then stabilizes at 40 MB in a 5-6 minutes.

Share this post


Link to post
Share on other sites
Hi.

Could it be an issue with GLUT ?

This part :
void timerCallback(int value)
{
glutPostRedisplay();
glutTimerFunc(5, timerCallback, 0);
}



Shouldn't be :

int main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
glutInitWindowPosition(300, 300);
glutInitWindowSize(640, 480);
int windowHandle = glutCreateWindow("Window");
glutDisplayFunc(paintGL);
glutReshapeFunc(changeSize);
glutTimerFunc(5, timerCallback, 0);
glutMainLoop();
glutDestroyWindow(windowHandle);
return 0;
}

void timerCallback(int value)
{
glutPostRedisplay();
}



? Edited by vNeeki

Share this post


Link to post
Share on other sites
No. I'm finding the same behavior with QGLWidget (not using GLUT). Also, VLC with OpenGL output seems to have this memory increase problem as well.

Share this post


Link to post
Share on other sites

[quote name='mhagain' timestamp='1329248389' post='4913090']
[quote name='mshafey' timestamp='1329247414' post='4913082']
Thanks for the suggestion. I've tried your code, it works, but it doesn't fix the leak. I'm still seeing memory leaking at the same rate on the affected platforms.

That's interesting. Let's try to pin down which call is causing it. What happens if you comment out the glTexSubImage2D call? And if you comment out the glMapBuffer block (but leave glTexSubImage2D in and coming from the PBO)?
[/quote]

gDEBugger with the code I posted in the first post. Upon application exit it says "Checking for memory leaks - Context 1 deleted. Memory Leak: 2 object(s) are leaked in GL Context 1 [Leak Size: 2,400KB]". Here are Process Explorer graphs for the original code running for a few minutes.

GPU graph: http://i.imgur.com/KgXix.png
Performance graph: http://i.imgur.com/bD9RH.png

I took out glMapBuffer()/glUnmapBuffer() block. Leak persists. Same for the glTexSubImage2D() call. Took them both out and still. Which lead me to remove everything except just basic calls to draw a rectangle switching colors. I'm sorry I sent everyone in the wrong direction here. It seems like even the most basic GL code causes Windows 7 machines to leak memory. I trimmed it down to this and it still leaks.



void paintGL();
void timerCallback(int value);
void changeSize(int w, int h);

unsigned char c = 255;

int main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
glutInitWindowPosition(300, 300);
glutInitWindowSize(640, 480);
int windowHandle = glutCreateWindow("Window");
glutDisplayFunc(paintGL);
glutReshapeFunc(changeSize);
timerCallback(0);
glutMainLoop();
glutDestroyWindow(windowHandle);
return 0;
}

void paintGL()
{
c = c? 0 : 255;
glColor3ub(c, c, c);
glBegin(GL_QUADS);
{
glVertex3f(-1, 1, 0);
glVertex3f(1, 1, 0);
glVertex3f(1, -1, 0);
glVertex3f(-1, -1, 0);
}
glEnd();

glutSwapBuffers();
}

void changeSize(int w, int h)
{
glViewport(0, 0, w, h);
}

void timerCallback(int value)
{
glutPostRedisplay();
glutTimerFunc(5, timerCallback, 0);
}



I might add that in some runs, this code starts off at about 18 MB and goes up to and then stabilizes at 40 MB in a 5-6 minutes.
[/quote]

This is crazy... I can't believe Intel drivers are this bad on windows... Well I ran into similar problems on windows when I worked for a company for the last summer, and eventually I had to switch to DirectX because the OGL functions just didn't work as expected (or caused crashes etc.)

Share this post


Link to post
Share on other sites
On reconsidering this, memory usage starting low, followed by an increase then stabilize is probably nothing to be worried about. It's where the stabilize part doesn't happen that you need to start worrying (that's a real leak - stabilization isn't a leak, it's just using resources). What's actually happening would be internal driver behaviour so we're reduced to guessing here, but going by your final stripped down program a reasonable and plausable guess would be that the driver is buffering up geometry used by immediate mode calls - it may for example be writing them into a dynamic VBO and then issuing real draw calls behind the scenes from that.

As for the two leaked objects - I have a suspicion which a simple test will help confirm. If you totally strip down the program so that each frame is nothing more than a clear and swapbuffers, and if they still leak, then I'm going to suggest that they might be your backbuffer and depth buffer (these do exist as actual GPU objects although OpenGL doesn't really expose them as such) - 640 * 480 * 4 * 2 is very close to the reported leak size of 2.4 mb (if my other guess is correct then the increase/stabilize usage pattern should also go away with this strip down). Of course, if gDEBugger allows you to drill further into this and identify which objects were leaked then it would be additional useful info.

Share this post


Link to post
Share on other sites

On reconsidering this, memory usage starting low, followed by an increase then stabilize is probably nothing to be worried about. It's where the stabilize part doesn't happen that you need to start worrying (that's a real leak - stabilization isn't a leak, it's just using resources). What's actually happening would be internal driver behaviour so we're reduced to guessing here, but going by your final stripped down program a reasonable and plausable guess would be that the driver is buffering up geometry used by immediate mode calls - it may for example be writing them into a dynamic VBO and then issuing real draw calls behind the scenes from that.


Thanks. We realized this is true. From here:


Memory Usage

[color=#000000][font=sans-serif]

It seems to be common to think that there is a memory leak in the OpenGL driver. Some users write simple programs such as this[/font]


[color=#000000][font=sans-serif]

glClear[color=#008000](...[color=#008000])[color=#008080];
SwapBuffers[color=#008000](...[color=#008000])[color=#008080];[/font]
[color=#000000][font=sans-serif]

and they observe that their memory usage goes up each time their Display function is called. That is normal. The driver might allocate some memory space and since the driver is basically a black box, we don't know what it is doing. The driver might be doing some work at optimizing in a secondary thread or preparing some buffering area. We don't know what it is doing, but there is no memory leak.[/font][/quote]

The problem is, in our application we're dealing with many OpenGL contexts at once (up to 30). For Windows XP on the same hardware, OpenGL memory is small compared to Windows 7. So in a day my application memory goes up to 1.5 GB on Win 7, but stays at 500 MB on XP.

We'll either require more memory or reduce the number of contexts used.

Thanks for the useful input everyone.

Share this post


Link to post
Share on other sites
Sign in to follow this  

  • Advertisement
  • Advertisement
  • Popular Tags

  • Advertisement
  • Popular Now

  • Similar Content

    • By reenigne
      For those that don't know me. I am the individual who's two videos are listed here under setup for https://wiki.libsdl.org/Tutorials
      I also run grhmedia.com where I host the projects and code for the tutorials I have online.
      Recently, I received a notice from youtube they will be implementing their new policy in protecting video content as of which I won't be monetized till I meat there required number of viewers and views each month.

      Frankly, I'm pretty sick of youtube. I put up a video and someone else learns from it and puts up another video and because of the way youtube does their placement they end up with more views.
      Even guys that clearly post false information such as one individual who said GLEW 2.0 was broken because he didn't know how to compile it. He in short didn't know how to modify the script he used because he didn't understand make files and how the requirements of the compiler and library changes needed some different flags.

      At the end of the month when they implement this I will take down the content and host on my own server purely and it will be a paid system and or patreon. 

      I get my videos may be a bit dry, I generally figure people are there to learn how to do something and I rather not waste their time. 
      I used to also help people for free even those coming from the other videos. That won't be the case any more. I used to just take anyone emails and work with them my email is posted on the site.

      I don't expect to get the required number of subscribers in that time or increased views. Even if I did well it wouldn't take care of each reoccurring month.
      I figure this is simpler and I don't plan on putting some sort of exorbitant fee for a monthly subscription or the like.
      I was thinking on the lines of a few dollars 1,2, and 3 and the larger subscription gets you assistance with the content in the tutorials if needed that month.
      Maybe another fee if it is related but not directly in the content. 
      The fees would serve to cut down on the number of people who ask for help and maybe encourage some of the people to actually pay attention to what is said rather than do their own thing. That actually turns out to be 90% of the issues. I spent 6 hours helping one individual last week I must have asked him 20 times did you do exactly like I said in the video even pointed directly to the section. When he finally sent me a copy of the what he entered I knew then and there he had not. I circled it and I pointed out that wasn't what I said to do in the video. I didn't tell him what was wrong and how I knew that way he would go back and actually follow what it said to do. He then reported it worked. Yea, no kidding following directions works. But hey isn't alone and well its part of the learning process.

      So the point of this isn't to be a gripe session. I'm just looking for a bit of feed back. Do you think the fees are unreasonable?
      Should I keep the youtube channel and do just the fees with patreon or do you think locking the content to my site and require a subscription is an idea.

      I'm just looking at the fact it is unrealistic to think youtube/google will actually get stuff right or that youtube viewers will actually bother to start looking for more accurate videos. 
    • By Balma Alparisi
      i got error 1282 in my code.
      sf::ContextSettings settings; settings.majorVersion = 4; settings.minorVersion = 5; settings.attributeFlags = settings.Core; sf::Window window; window.create(sf::VideoMode(1600, 900), "Texture Unit Rectangle", sf::Style::Close, settings); window.setActive(true); window.setVerticalSyncEnabled(true); glewInit(); GLuint shaderProgram = createShaderProgram("FX/Rectangle.vss", "FX/Rectangle.fss"); float vertex[] = { -0.5f,0.5f,0.0f, 0.0f,0.0f, -0.5f,-0.5f,0.0f, 0.0f,1.0f, 0.5f,0.5f,0.0f, 1.0f,0.0f, 0.5,-0.5f,0.0f, 1.0f,1.0f, }; GLuint indices[] = { 0,1,2, 1,2,3, }; GLuint vao; glGenVertexArrays(1, &vao); glBindVertexArray(vao); GLuint vbo; glGenBuffers(1, &vbo); glBindBuffer(GL_ARRAY_BUFFER, vbo); glBufferData(GL_ARRAY_BUFFER, sizeof(vertex), vertex, GL_STATIC_DRAW); GLuint ebo; glGenBuffers(1, &ebo); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo); glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices,GL_STATIC_DRAW); glVertexAttribPointer(0, 3, GL_FLOAT, false, sizeof(float) * 5, (void*)0); glEnableVertexAttribArray(0); glVertexAttribPointer(1, 2, GL_FLOAT, false, sizeof(float) * 5, (void*)(sizeof(float) * 3)); glEnableVertexAttribArray(1); GLuint texture[2]; glGenTextures(2, texture); glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, texture[0]); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); sf::Image* imageOne = new sf::Image; bool isImageOneLoaded = imageOne->loadFromFile("Texture/container.jpg"); if (isImageOneLoaded) { glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, imageOne->getSize().x, imageOne->getSize().y, 0, GL_RGBA, GL_UNSIGNED_BYTE, imageOne->getPixelsPtr()); glGenerateMipmap(GL_TEXTURE_2D); } delete imageOne; glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_2D, texture[1]); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); sf::Image* imageTwo = new sf::Image; bool isImageTwoLoaded = imageTwo->loadFromFile("Texture/awesomeface.png"); if (isImageTwoLoaded) { glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, imageTwo->getSize().x, imageTwo->getSize().y, 0, GL_RGBA, GL_UNSIGNED_BYTE, imageTwo->getPixelsPtr()); glGenerateMipmap(GL_TEXTURE_2D); } delete imageTwo; glUniform1i(glGetUniformLocation(shaderProgram, "inTextureOne"), 0); glUniform1i(glGetUniformLocation(shaderProgram, "inTextureTwo"), 1); GLenum error = glGetError(); std::cout << error << std::endl; sf::Event event; bool isRunning = true; while (isRunning) { while (window.pollEvent(event)) { if (event.type == event.Closed) { isRunning = false; } } glClear(GL_COLOR_BUFFER_BIT); if (isImageOneLoaded && isImageTwoLoaded) { glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, texture[0]); glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_2D, texture[1]); glUseProgram(shaderProgram); } glBindVertexArray(vao); glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, nullptr); glBindVertexArray(0); window.display(); } glDeleteVertexArrays(1, &vao); glDeleteBuffers(1, &vbo); glDeleteBuffers(1, &ebo); glDeleteProgram(shaderProgram); glDeleteTextures(2,texture); return 0; } and this is the vertex shader
      #version 450 core layout(location=0) in vec3 inPos; layout(location=1) in vec2 inTexCoord; out vec2 TexCoord; void main() { gl_Position=vec4(inPos,1.0); TexCoord=inTexCoord; } and the fragment shader
      #version 450 core in vec2 TexCoord; uniform sampler2D inTextureOne; uniform sampler2D inTextureTwo; out vec4 FragmentColor; void main() { FragmentColor=mix(texture(inTextureOne,TexCoord),texture(inTextureTwo,TexCoord),0.2); } I was expecting awesomeface.png on top of container.jpg

    • By khawk
      We've just released all of the source code for the NeHe OpenGL lessons on our Github page at https://github.com/gamedev-net/nehe-opengl. code - 43 total platforms, configurations, and languages are included.
      Now operated by GameDev.net, NeHe is located at http://nehe.gamedev.net where it has been a valuable resource for developers wanting to learn OpenGL and graphics programming.

      View full story
    • By TheChubu
      The Khronos™ Group, an open consortium of leading hardware and software companies, announces from the SIGGRAPH 2017 Conference the immediate public availability of the OpenGL® 4.6 specification. OpenGL 4.6 integrates the functionality of numerous ARB and EXT extensions created by Khronos members AMD, Intel, and NVIDIA into core, including the capability to ingest SPIR-V™ shaders.
      SPIR-V is a Khronos-defined standard intermediate language for parallel compute and graphics, which enables content creators to simplify their shader authoring and management pipelines while providing significant source shading language flexibility. OpenGL 4.6 adds support for ingesting SPIR-V shaders to the core specification, guaranteeing that SPIR-V shaders will be widely supported by OpenGL implementations.
      OpenGL 4.6 adds the functionality of these ARB extensions to OpenGL’s core specification:
      GL_ARB_gl_spirv and GL_ARB_spirv_extensions to standardize SPIR-V support for OpenGL GL_ARB_indirect_parameters and GL_ARB_shader_draw_parameters for reducing the CPU overhead associated with rendering batches of geometry GL_ARB_pipeline_statistics_query and GL_ARB_transform_feedback_overflow_querystandardize OpenGL support for features available in Direct3D GL_ARB_texture_filter_anisotropic (based on GL_EXT_texture_filter_anisotropic) brings previously IP encumbered functionality into OpenGL to improve the visual quality of textured scenes GL_ARB_polygon_offset_clamp (based on GL_EXT_polygon_offset_clamp) suppresses a common visual artifact known as a “light leak” associated with rendering shadows GL_ARB_shader_atomic_counter_ops and GL_ARB_shader_group_vote add shader intrinsics supported by all desktop vendors to improve functionality and performance GL_KHR_no_error reduces driver overhead by allowing the application to indicate that it expects error-free operation so errors need not be generated In addition to the above features being added to OpenGL 4.6, the following are being released as extensions:
      GL_KHR_parallel_shader_compile allows applications to launch multiple shader compile threads to improve shader compile throughput WGL_ARB_create_context_no_error and GXL_ARB_create_context_no_error allow no error contexts to be created with WGL or GLX that support the GL_KHR_no_error extension “I’m proud to announce OpenGL 4.6 as the most feature-rich version of OpenGL yet. We've brought together the most popular, widely-supported extensions into a new core specification to give OpenGL developers and end users an improved baseline feature set. This includes resolving previous intellectual property roadblocks to bringing anisotropic texture filtering and polygon offset clamping into the core specification to enable widespread implementation and usage,” said Piers Daniell, chair of the OpenGL Working Group at Khronos. “The OpenGL working group will continue to respond to market needs and work with GPU vendors to ensure OpenGL remains a viable and evolving graphics API for all its customers and users across many vital industries.“
      The OpenGL 4.6 specification can be found at https://khronos.org/registry/OpenGL/index_gl.php. The GLSL to SPIR-V compiler glslang has been updated with GLSL 4.60 support, and can be found at https://github.com/KhronosGroup/glslang.
      Sophisticated graphics applications will also benefit from a set of newly released extensions for both OpenGL and OpenGL ES to enable interoperability with Vulkan and Direct3D. These extensions are named:
      GL_EXT_memory_object GL_EXT_memory_object_fd GL_EXT_memory_object_win32 GL_EXT_semaphore GL_EXT_semaphore_fd GL_EXT_semaphore_win32 GL_EXT_win32_keyed_mutex They can be found at: https://khronos.org/registry/OpenGL/index_gl.php
      Industry Support for OpenGL 4.6
      “With OpenGL 4.6 our customers have an improved set of core features available on our full range of OpenGL 4.x capable GPUs. These features provide improved rendering quality, performance and functionality. As the graphics industry’s most popular API, we fully support OpenGL and will continue to work closely with the Khronos Group on the development of new OpenGL specifications and extensions for our customers. NVIDIA has released beta OpenGL 4.6 drivers today at https://developer.nvidia.com/opengl-driver so developers can use these new features right away,” said Bob Pette, vice president, Professional Graphics at NVIDIA.
      "OpenGL 4.6 will be the first OpenGL release where conformant open source implementations based on the Mesa project will be deliverable in a reasonable timeframe after release. The open sourcing of the OpenGL conformance test suite and ongoing work between Khronos and X.org will also allow for non-vendor led open source implementations to achieve conformance in the near future," said David Airlie, senior principal engineer at Red Hat, and developer on Mesa/X.org projects.

      View full story
    • By _OskaR
      Hi,
      I have an OpenGL application but without possibility to wite own shaders.
      I need to perform small VS modification - is possible to do it in an alternative way? Do we have apps or driver modifictions which will catch the shader sent to GPU and override it?
  • Advertisement