Time multiplexed redundant array of independent tapes

A method for storing data on a time multiplexed redundant array of independent tapes, the method comprising

• receiving a series of data blocks to be written to a set of tape data storage devices in a tape-sequential manner;
• sequentially writing a first number of the series of data blocks to a first tape;
• setting a tape length variable to the first number;
• sequentially writing a second number of the series of data blocks to a second tape;
• based on a determination that the second number is less that the tape length variable, setting the tape length variable to the second number and marking a subset of the first number of data blocks that exceeds the tape length variable as not written to the first tape;
• sequentially writing a third number of the series of data blocks to a third tape, the third number of the series of data blocks including the subset of the first number of the series of data blocks;
• forming a number of parity stripes of blocks across the first tape, the second tape, and the third tape and calculating a parity data value for each of the parity stripes;
• and
• sequentially writing the parity data values to a fourth tape.

A computer program product for storing data on a time multiplexed redundant array of independent tapes, the computer program product comprising a computer readable storage medium having program code embodied therewith, the program code executable by a processor to:

• receive a series of data blocks to be written to a set of tape data storage devices in a tape-sequential manner;
• sequentially write a first number of the series of data blocks to a first tape;
• set a tape length variable to the first number;
• sequentially write a second number of the series of data blocks to a second tape;
• based on a determination that the second number is less that the tape length variable, set the tape length variable to the second number and mark a subset of the first number of data blocks that exceeds the tape length variable as not written to the first tape;
• sequentially write a third number of the series of data blocks to a third tape, the third number of the series of data blocks including the subset of the first number of the series of data blocks;
• form a number of parity stripes of blocks across the first tape, the second tape, and the third tape and calculating a parity data value for each of the parity stripes;
• and
• sequentially write the parity data values to a fourth tape.