A disk drive measures the radial misposition of tracks and repositions the tracks
at regularly spaced intervals. Written in runout (WRO) in servo bursts is determined
to calculate track spacing and squeeze among adjacent tracks. Tracks with improper
spacing are repositioned by adding a squeeze correction term to the servo wedges.
Thereafter, when the disk drive operates to store data, the servo bursts are used
to calculate a position error signal (PES), and the squeeze correction term is
combined with the PES to position the head at a proper track radius.