Tape Storage Device and Writing Method Therefor

摘要

A mechanism is provided for tape writing of small transactions. A first file is written as a plurality of fixed-length data sets (DS), the DS number of the final DS in the plurality of DS is stored in memory as #IN(DS#N) and the WP number as #M(WP#M), and the final first file and the second file in the DS following the final DS(DS#N, WP#M) containing the first file are packed and written in sequential DS units, and are stored as DS#N, DS#N+1, etc. and WP#M+1 in sequential order in DS containing the second file. The remaining first, second, or third file is packed and DS#N with WP#M is overwritten as DS#N with WP#M+2, and the remaining #N in the DS numbers of the second file and the third file in the subsequent DS are written as DS#N+1, N+2, etc. with WP#M+2, and the DS#N, #N+2, etc. with WP#M+2 are stored.

主权项

1. A method, in a data processing system for writing files of less than fixed length to a tape medium, the method comprising:
writing a first file from a host to the tape medium as a set of datasets (DSs) when receiving files from the host; storing a DS number (DS#N) of a last DS and a WritePass (WP) number #M (WP#M) of a last write operation to nonvolatile memory, wherein the non-volatile memory is cartridge memory (CM) in which a cartridge contains the tape medium; sequentially writing DSs filled with the first file and a second file to a DS following the last DS containing the first file to the tape medium when receiving the second file following the first file; assigning incremental DS numbering and WP number #M+1 to the DSs containing the second file and the first file; and storing the DS numbers and the WP number associated with first file and the second file to the nonvolatile memory.