{HEAD ~ The data} are migrated into RAID 5 configurations as {TAIL ~ a background operation}, to minimize the disk space lost 
are migrated as
{ HEAD ~ The data } are migrated into RAID 5 configurations as { TAIL ~ a background operation } , to minimize the disk space lost
HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH