# Excess memory usage when visualising vtkCubes or other objects

**URL:** https://discourse.vtk.org/t/excess-memory-usage-when-visualising-vtkcubes-or-other-objects/3923
**Category:** Support
**Created:** [August 6, 2020, 9:04am UTC](https://discourse.vtk.org/t/excess-memory-usage-when-visualising-vtkcubes-or-other-objects/3923 "2020-08-06T09:04:43Z")
**Posts on this page:** 5
**Page:** 1

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### Author: ![mastrogiorgis](https://discourse.vtk.org/user_avatar/discourse.vtk.org/mastrogiorgis/32/3167_2.png) [@mastrogiorgis](https://discourse.vtk.org/u/mastrogiorgis)
#### Post date: [August 6, 2020, 9:04am UTC](https://discourse.vtk.org/t/excess-memory-usage-when-visualising-vtkcubes-or-other-objects/3923/1 "2020-08-06T09:04:43Z")

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Hi,

I noticed an excessive usage of memory when using vtkCubes to visualise an 8x8x2 blocks as seen in the image.

 ![blocks8x8x2](https://discourse.vtk.org/uploads/default/original/2X/a/a17f700f046cc03f27238e8e6e3e16b15f5d78f3.jpeg)  
The memory usage is ~ 380Mb  
 ![memoryUsage](https://discourse.vtk.org/uploads/default/original/2X/1/12e3fd2e30fe0d804e0d93526d37188adf4fa9c5.jpeg)

Is there anything I can try to reduce this?  
Many thanks.

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### Author: ![lassoan](https://discourse.vtk.org/user_avatar/discourse.vtk.org/lassoan/32/50_2.png) [@lassoan](https://discourse.vtk.org/u/lassoan)
#### Post date: [August 6, 2020, 12:14pm UTC](https://discourse.vtk.org/t/excess-memory-usage-when-visualising-vtkcubes-or-other-objects/3923/2 "2020-08-06T12:14:08Z")

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380MB total memory usage for a 3D visualization application is pretty good. You may be able to reduce it by loading only certain VTK modules, but probably this would require VTK9 and/or custom VTK build.

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### Author: ![mastrogiorgis](https://discourse.vtk.org/user_avatar/discourse.vtk.org/mastrogiorgis/32/3167_2.png) [@mastrogiorgis](https://discourse.vtk.org/u/mastrogiorgis)
#### Post date: [August 6, 2020, 2:42pm UTC](https://discourse.vtk.org/t/excess-memory-usage-when-visualising-vtkcubes-or-other-objects/3923/3 "2020-08-06T14:42:17Z")

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Hi Andras and thanks for the info. I noticed that cubes take a while to visualisation when I get a 25x25x6 sized geometry. Is there a way I can accelerate this as I thought it was a memory issue at first.

PS. The memory when visualising the 25x25x6 is about 800mb

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### Author: ![lassoan](https://discourse.vtk.org/user_avatar/discourse.vtk.org/lassoan/32/50_2.png) [@lassoan](https://discourse.vtk.org/u/lassoan)
#### Post date: [August 6, 2020, 3:51pm UTC](https://discourse.vtk.org/t/excess-memory-usage-when-visualising-vtkcubes-or-other-objects/3923/4 "2020-08-06T15:51:31Z")

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If you use a GUI toolkit as well then 800MB is understandable, but otherwise it seems a bit too high (if 25x25x6 means you visualize 25x25x6=3750 cells, which is nearly zero amount of data). Maybe you import a lot of libraries that are not strictly needed, which takes time and memory. To see what’s going on, you can have a look at the list of loaded shared libraries (see instructions for Windows [here](https://kb.froglogic.com/misc/getting-list-of-loaded-dlls/)).

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### Author: ![mastrogiorgis](https://discourse.vtk.org/user_avatar/discourse.vtk.org/mastrogiorgis/32/3167_2.png) [@mastrogiorgis](https://discourse.vtk.org/u/mastrogiorgis)
#### Post date: [March 21, 2021, 10:45pm UTC](https://discourse.vtk.org/t/excess-memory-usage-when-visualising-vtkcubes-or-other-objects/3923/5 "2021-03-21T22:45:21Z")

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Hi again,  
Revisiting this topic due to a similar but a bit confusing memory usage issue.

 ![image](https://discourse.vtk.org/uploads/default/original/2X/d/d41f1bbb8606405155a5e6bd9ef50392c3088b33.png)

 ![image](https://discourse.vtk.org/uploads/default/original/2X/a/a4cc7107f452ad935d8e28c796dcf651e1e061ed.png)

I noticed that the mem usage fires up (from 400 to 480mb) when I move/zoom in-out the vtkCubes drawing in a PyQt window while the mem usage remains the same if I use the vtk native one.

I’m using the QVTKRenderWindowInteractor.  
Is this an expected behaviour?  
Many thanks,