3D data isn't release from RAM when loaded in VRAM

I had to implement my own texture format loader and I saw that the API doesn't allow Qt3D to be able to release the texture buffer loaded in RAM after the transfer to the VRAM.

I think that is a big issue for small devices and will be a blocker for us, because the Qt3D version of our application consume twice more memory than with our actual home-brew 3D engine.

Our texture are compressed and can't be used for any other thing than the rendering.
For meshes it is little different because it can be used for the picking or something else, but in our engine, it's completely separated of the rendering to duplicate geometries in an optimal format. Picking doesn't request same data, texcoords or normals aren't always necessary.

PS: It seems that there is the same issue with the QtQuick renderer.