Patent ID: 8312210

Claim:
A computer program product comprising a computer useable medium having a computer readable program stored on a tangible storage device, wherein the computer readable program when executed on a computer causes the computer to: compress a data file organized in logical tracks; determine a track compression ratio wherein the track compression ratio is a ratio of an integer value n to one; destage only a single directory entry for the data file to a directory, wherein the directory entry comprises only a logical name for the data file and a single zeroth track location z on a hard disk drive; destage the data file sequentially to tracks of the hard disk drive from the zeroth track with n logical tracks of the data file stored on one physical track of the hard disk drive; and stage a logical track with a logical track number of k from a physical track of the hard disk drive specified by a location q using only the zeroth track location z, the track compression ratio n, and k, wherein q is calculated as q=(INTEGER(k/n))+z and (INTEGER(k/n)) is an integer value of (k/n).