1. A storage system comprising: a storage processor coupled to a host through a PCIe switch and a storage pool made of PCIe solid storage disks (SSDs), the storage processor including; a central processing unit (CPU) subsystem; a PCIe switch coupled to the CPU subsystem; and memory configured to save tables, the CPU subsystem operable to communicate with the host and the storage pool through the PCIe switch, the CPU subsystem being operable to: receive a command from the host to write data, identified by logical block addresses, to the storage pool, the data organized into logical block address (LBA) logical units (LUNs) groups with each group size being no less than a predetermined granularity, responsive to the command, determine a number of LUN LBA-groups being added, based on the number of LUN LBA groups being added, identify free locations within the storage pool addressed by storage pool free LBA-groups, the free locations accommodating storage of added data associated with the LUN LBA groups being added, the identified free locations being used to store at least a portion of the data in the storage pool, at the location therein identified by the storage pool free LBA-groups, and upon being identification, the storage pool free LBA-groups becoming storage pool LBA-groups, link the storage pool free LBA-groups to the LUN LBA-groups being updating a mapping table included in the tables to add the LUN LBA-groups by using the LUN LBA-groups to index the LUN LBA-groups, access the storage pool to write the data by using the storage pool LBA-groups, wherein the size of the mapping table is larger to accommodate for the addition of LUNs.