Detecting damaged areas on magnetic tape based on measuring number of servo errors

Patent metadata

Field	Value
Publication number	US-10497394-B2
Application number	US-201916269424-A
Country	US
Kind code	B2
Filing date	Feb 6, 2019
Priority date	Dec 20, 2017
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

A computer-implemented method for determining a damaged area of a magnetic tape loaded in a tape drive, according to one embodiment, includes: determining a first error location on a magnetic tape where a first error occurred in response to experiencing the first error. Moreover, the method includes determining one or more areas on the magnetic tape to be examined. The one or more areas are determined using a predetermined algorithm which incorporates the first error location. Independent of a read and/or write operation, relative motion is induced between a tape head and the magnetic tape such that the tape head is positioned adjacent to each of the respective one or more areas in turn. Furthermore, each of the one or more areas having a respective number of measured servo errors which exceeds a threshold value is identified as a damaged area of the magnetic tape.

First claim

What is claimed is:

1. A computer program product for determining a damaged area of a magnetic tape loaded in a tape drive, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions readable and/or executable by a processor to cause the processor to:
determine, by the processor, a first error location on a magnetic tape where a first error occurred in response to experiencing the first error;
determine, by the processor, one or more areas on the magnetic tape to be examined, wherein the one or more areas are determined using a predetermined algorithm which incorporates the first error location;
independent of a read and/or write operation, induce, by the processor, relative motion between a tape head and the magnetic tape such that the tape head is positioned adjacent to each of the respective one or more areas in turn; and
identify, by the processor, each of the one or more areas having a respective number of measured servo errors which exceeds a threshold value as a damaged area of the magnetic tape.

2. The computer program product as recited in claim 1 , wherein the one or more areas on the magnetic tape to be examined includes a first area, wherein the first area is located adjacent to an area containing the first error location, wherein the first area is located in a same wrap of the magnetic tape as the area containing the first error location, wherein the program instructions are readable and/or executable by the processor to cause the processor to:
use, by the processor, the tape head to measure a number of servo errors that occur in each of the respective one or more areas, by:
using the tape head to measure a number of servo errors that occur in the first area,
in response to determining that the number of servo errors measured in the first area exceeds the threshold value, performing an iterative process which includes:
using the tape head to measure the number of servo errors that occur in a next area on the magnetic tape, wherein the next area is located longitudinally adjacent to a previously measured area of the magnetic tape determined to have a number of servo errors which exceeded the threshold value; and
determining whether the number of servo errors that occur in the next area on the magnetic tape exceeds the threshold value, and

terminating the iterative process in response to determining that the number of servo errors that occur in the next area on the magnetic tape does not exceed the threshold value.

3. The computer program product as recited in claim 1 , the program instructions readable and/or executable by the processor to cause the processor to:
cause by the processor, information indicating the identified damaged areas of the magnetic tape to be recorded in a cartridge memory.

4. A computer-implemented method for determining a damaged area of a magnetic tape loaded in a tape drive, the method comprising:
determining a first error location on a magnetic tape where a first error occurred in response to experiencing the first error;
determining one or more areas on the magnetic tape to be examined, wherein the one or more areas are determined using a predetermined algorithm which incorporates the first error location;
independent of a read and/or write operation, inducing relative motion between a tape head and the magnetic tape such that the tape head is positioned adjacent to each of the respective one or more areas in turn; and
identifying each of the one or more areas having a respective number of measured servo errors which exceeds a threshold value as a damaged area of the magnetic tape.

5. The computer-implemented method as recited in claim 4 , comprising:
determining one or more areas on a second wrap of the magnetic tape to be examined, wherein the second wrap is adjacent to a first wrap of the magnetic tape which includes the first error location, wherein the one or more areas are determined using the predetermined algorithm;
independent of a read and/or write operation, inducing relative motion between the tape head and the magnetic tape such that the tape head is positioned adjacent to each of the respective one or more areas on the second wrap in turn;
using the tape head to measure a number of servo errors that occur in each of the respective one or more areas on the second wrap; and
identifying each of the one or more areas on the second wrap having a respective number of measured servo errors which exceeds the threshold value as a damaged area of the magnetic tape.

6. The computer-implemented method as recited in claim 4 , comprising:
in response to identifying all of the one or more areas as damaged areas, performing the following process:
determining one or more areas on a wrap of the magnetic tape to be examined, wherein the wrap is located in a different data band than a data band containing the first error location, wherein the one or more areas on the wrap are determined using the predetermined algorithm;
independent of a read and/or write operation, inducing relative motion between the tape head and the magnetic tape such that the tape head is positioned adjacent to each of the respective one or more areas on the wrap in turn;
using the tape head to measure a number of servo errors that occur in each of the respective one or more areas on the wrap; and
identifying each of the one or more areas on the wrap having a respective number of measured servo errors which exceeds the threshold value as a damaged area of the magnetic tape.

7. A computer-implemented method for determining a damaged area of a magnetic tape loaded in a tape drive, the method comprising:
receiving, from the tape drive, a first error location on the magnetic tape where a first error occurred in response to the tape drive experiencing the first error;
determining one or more areas on the magnetic tape to be examined, wherein the one or more areas are determined using a predetermined algorithm which incorporates the first error location;
independent of a read and/or write operation, instructing the tape drive to induce relative motion between a tape head and the magnetic tape such that the tape head is positioned adjacent to each of the respective one or more areas in turn; and
identifying each of the one or more areas having a respective number of measured servo errors which exceeds a threshold value as a damaged area of the magnetic tape.

8. The computer-implemented method as recited in claim 7 , comprising:
making a backup copy of data stored in the identified damaged area(s) of the magnetic tape by copying the data from a buffer memory or another storage medium having a copy of the data stored in the identified damaged area(s) of the magnetic tape, wherein the backup copy is stored on a second magnetic tape.

9. A computer program product for determining a damaged area of a magnetic tape loaded in a tape drive, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions readable and/or executable by a processor to cause the processor to:
receive, by the processor, a first error location on the magnetic tape where a first error occurred in response to the tape drive experiencing the first error;
determine, by the processor, one or more areas on the magnetic tape to be examined, wherein the one or more areas are determined using a predetermined algorithm which incorporates the first error location;
independent of a read and/or write operation, instruct, by the processor, the tape drive to induce relative motion between a tape head and the magnetic tape such that the tape head is positioned adjacent to each of

Assignees

• IBM

Inventors

• Yamamoto Noriko
• Miyamura Tsuyoshi
• Itagaki Hiroshi
• Hasegawa Tohru
• Matsui Sosuke
• Mitsuma Shinsuke

Classifications

• G11B20/1886 Primary

  with tapes · CPC title

• G11B5/5513

  Specially adapted for transducing in both travelling directions of tape · CPC title

• G11B2020/1826

  wherein a defect list or error map is generated · CPC title

• G11B27/30

  on the same track as the main recording · CPC title

• G11B5/584

  for track following on tapes · CPC title