Technique for providing information on time to read a file

A method executed by an information providing system for providing time taken to read a file, the method comprising:

• obtaining information on a recording position of a file when the file is recorded in a storage device, using an acquisition unit, the storage device being a mountable magnetic tape medium;
• writing information on the obtained recording position to an index, the index being referred to when accessing the file, and when accessing the file the obtained recording position being written to the index contemporaneously with the file being recorded in the storage device, the recording position of the file written to the index being recorded separate from the recorded file, and the index which includes the recording position being stored in another storage device other than with the recorded file;
• obtaining an actual position of the file recorded in the storage device, using the acquisition unit, for the recording position of the file, the actual position includes a WRAP (lateral direction perpendicular to the longitudinal direction) and LPOS (longitudinal direction of a tape) at the start of writing and WRAP and LPOS at the end of writing;
• calculating time taken to read the file using the information on the recording position written to the index in response to a request to obtain the time taken to read the file, when the tape medium is not mounted, the calculating of the time taken to read the file including a recording start position and a recording end position for the file written to the index, the calculation unit calculating the time from the start position of data reading to the end position using the recorded start position and the recorded end position written to the index without subsequently accessing the storage device after receiving the request to obtain the time taken to read the file;
• and
• providing the calculated time to a requestor that initiated the request to obtain the time to read the file when the tape medium is not mounted, thereby providing the calculated time to read the file without accessing the storage device after receiving the request to obtain the time taken to read the file.

A computer program product for providing time taken to read a file, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a computer to cause the computer to perform a method, comprising:

• obtaining information on a recording position of a file when the file is recorded in a storage device, using an acquisition unit, the storage device being a mountable magnetic tape medium;
• writing information on the obtained recording position to an index, the index being referred to when accessing the file, and when accessing the file the obtained recording position being written to the index contemporaneously with the file being recorded in the storage device, the recording position of the file written to the index being recorded separate from the recorded file, and the index which includes the recording position being stored in another storage device other than with the recorded file, the recording position of the file being an actual position of the file recorded in the storage device and the actual position being obtained using the acquisition unit, the actual position includes a WRAP (lateral direction perpendicular to the longitudinal direction) and LPOS (longitudinal direction of a tape) at the start of writing and WRAP and LPOS at the end of writing;
• calculating time taken to read the file using the information on the recording position written to the index in response to a request to obtain the time taken to read the file, when the tape medium is not mounted, the calculating of the time taken to read the file including a recording start position and a recording end position for the file written to the index, the calculation unit calculating the time from the start position of data reading to the end position using the recorded start position and the recorded end position written to the index without subsequently accessing the storage device after receiving the request to obtain the time taken to read the file;
• and
• providing the calculated time to a requestor that initiated the request to obtain the time to read the file when the tape medium is not mounted, thereby providing the calculated time to read the file without accessing the storage device after receiving the request to obtain the time taken to read the file.