Shingled magnetic recording disk drive with inter-band disk cache and minimization of the effect of far track erasure on adjacent data bands

• Main Authors: HARAYAMA TOMOHIRO, MATEESCU ROBERT EUGENIU, THORSTENSON SHAD HENRY, BANDIC ZVONIMIR Z, TSAI TIMOTHY KOHCHIH, GUYOT CYRIL
• Format: Patent
• Language: English
• Published: 29.07.2014
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

A shingled magnetic recording hard disk drive that uses writeable cache tracks in the inter-band gaps between the annular data bands minimizes the effect of far track erasure (FTE) in the boundary regions of annular data bands caused by writing to the cache tracks. Based on the relative FTE effect for all the tracks in a range of tracks of the cache track being written, a count increment (CI) table or a cumulative count increment (CCI) table is maintained. For every writing to a cache track, a count for each track in an adjacent boundary region, or a cumulative count for each adjacent boundary region, is increased. When the count value for a track, or the cumulative count for a boundary region, reaches a predetermined threshold the data is read from that band and rewritten to the same band.