One of the topics discussed for each filesystem is how large a volume can you put on it. For most of them, that number is 16 TB, a shared artifact of using 32-bit numbers to represent filesystem information. Right now, it's quite easy to exceed 16 TB in a volume created with a moderately sized array of 1 TB or larger hard drives. This makes this number an increasingly problematic limit.
There are three levels of issue you can run into here:
- The data structures of the filesystem itself don't support large volumes
- Tools used to create and manipulate the filesystem do not handle large sizes
- The disk partitioning scheme needed to boot the operating system (OS) doesn't handle large volumes
The last of those is worth spending a moment on, since that problem is mostly independent of the filesystem-specific details of the first two.
Most PC hardware...