Maximum size of PLY / pointcloud

[pimbongaerts]

Just wondering whether there is a maximum size for PLY files and/or point clouds that can be opened in Open3D? In a script that iterates over point clouds (to do local searches around annotation points), I can open (open3d.io.read_point_cloud) PLY files up to 54 GB in size (~2B vertices), but larger files (eg 61GB and 65GB; 2,3B+ vertices) fail to load and I get a [Open3D WARNING] Read PLY failed: number of vertex <= 0.. The files do not seem to be corrupted (I can open them using CloudCompare CLI), and RAM also does not (yet) seem to be the issue: loading the 54 GB file uses 131GB of RAM (total RAM on the machine is 256GB; AMD Ryzen 3970X).