US Patent 9418699 Management of sequentially written data

A Data Storage Device (DSD) includes a disk with a zone of tracks to be sequentially written. A sequential write pointer is maintained indicating a next physical location for writing data in the zone. When a write command is received to write data in a target region at a physical location behind the sequential write pointer, it is determined whether a write count for each of the target region and an adjacent region before the target region has reached a threshold number of writes. If it is determined that the write counts for both the target region and the adjacent region have not reached the threshold number of writes, the sequential write pointer for the zone is moved to the physical location and the data is written at the physical location to fulfill the write command.