1. A computer-implemented method of optimizing storage space usage, the computer-implemented method comprising: receiving, by one or more processors implementing a Smart Volume Manager, an input/output (I/O) client process, wherein the I/O client process requests an I/O action from a file system storage device; determining, by one or more processors implementing the Smart Volume Manager, that the file system storage device is operating at 100% capacity; in response to determining that the file system storage device is operating at 100% capacity, generating, by one or more processors implementing the Smart Volume Manager, a dynamic virtual buffer disk group from multiple donor disk groups; and redirecting, by one or more processors implementing the Smart Volume Manager, the I/O client process to the dynamic virtual buffer disk group, wherein the dynamic virtual buffer disk group is appended to the file system storage device to create an extended filesystem volume.