When a read or write request is received, {TAIL ~ adaptive RAID mapping data structures} are used to map the blocks requested by the host into {HEAD ~ the blocks} managed by the transparent RAID 
When a read or write request is received , { TAIL ~ adaptive RAID mapping data structures } are used to map the blocks requested by the host into { HEAD ~ the blocks } managed by the transparent RAID
OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH