I am working on a linux-based c++ OpenGL application, utilizing the Nvidia 290.10 64bit drivers. I am trying to reduce its memory footprint as it makes use of quite a lot of live data.
I've been using valgrind/massif to analyze heap usage, and while it helped me optimize various things, by now the largest chunk of heap memory used is allocated by libGL. No matter how I set the threshold, massif doesn't let me see in detail where those allocations come from, just that it's libGL. At peak times, I see about 250MB allocated by libGL (out of 900MB total heap usage). I hold a similar amount of memory on the graphics card, as VBOs and Textures (mostly one big 4096*4096 texture).
So it appears as if a similar amount of memory as what I upload to GPU memory is allocated on the heap by libGL. The libGL allocations also peak when the volume of VBOs peaks. Is that normal? I thought one of the benefits of having a lot of GPU memory is that it keeps the RAM free?
Copyright Notice：Content Author:「pholz」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/10698125/libgl-heap-usage