Have you spent time search the VMware documentation, on-line forums, venues and books to decide how to make a local dedicated direct attached storage (DAS) type device (e.g. SATA or SAS) be Raw Device Mappings (RDM)? Or how about how to make a Hybrid Hard disk drive (HHDD) that is faster than a regular Hard Disk Drive (HDD) on reads, however more capacity and less cost than a Solid State Device (SSD) actually appear to VMware as a SSD?