In case it wasn't immediately clear, this is referring to the NP-hard problem of allocating objects (of a particular volume and size) to bins (also of a particular volume and size) in the most efficient possible way [1], as apposed to being a binary packer [2]
[1] https://en.wikipedia.org/wiki/Bin_packing_problem [2] https://en.wikipedia.org/wiki/Executable_compression