System, method and computer program product for partially synchronous and partially asynchronous mounts/unmounts in a media library

• US 9,934,243 B2
• Filed: 06/16/2015
• Issued: 04/03/2018
• Est. Priority Date: 09/13/2012
• Status: Active Grant

• Current Assignee: KIP CR P1 LP
• Original Assignee: KIP CR P1 LP
• Inventors: Kick, Damien
• Primary Examiner(s): Alam, Hosain
• Assistant Examiner(s): Allen, Nicholas
• Application Number:
  US14/741,220
• Publication Number:
  US 20150286654A1
• Time in Patent Office: 1,022 Days
• Field of Search: 707613
• CPC Class Codes: G06F 16/1774 Locking methods, e.g. locking methods for file systems allowing shared and concurrent access to files
• CPC Class Codes: G06F 16/178 Techniques for file synchronisation in file systems

Abstract

Systems, methods and computer program products for determining completion of commands in a library system and providing an indication of the completion to a component of the media library system so that other commands which are dependent upon the completion can be efficiently issued and executed. In one embodiment, a tape is mounted in a drive of the library and a filesystem mount command is issued to initiate a filesystem mount operation. Diagnostic information generated by the operating system for this operation is communicated to the media library management application. When the filesystem mount process is completed, a corresponding diagnostic message is communicated to the media library management application. Until this message is received by the media library management application, commands that are dependent upon the completion of the filesystem mount process are inhibited, and afterward these dependent commands are allowed to be issued.

Claims

1. A method for media library management, comprising:

a media library management application communicating with a host device to enable the host device access to a media library that includes a plurality of media selectively mountable in one or more drives of the media library, the media library management application executing on an appliance having a computer processor, a memory coupled to the computer processor, and an operating system executing on the computer processor;

the media library management application initiating an unmount process to unmount a currently mounted medium of the plurality of media in the media library from a drive in the media library, the currently mounted medium having a currently mounted filesystem;

responsive to the media library management application initiating the unmount process, the operating system initiating an unmount operation to unmount the currently mounted filesystem, wherein until the unmount operation is complete, a wait process running in a monitor thread created by the media library management application and a filesystem process remain pending, the wait process configured to monitor the filesystem process for a change in state, wherein when the unmount operation is complete, the filesystem process terminates;

responsive to termination of the filesystem process, the wait process sending a notification to the media library management application; and

responsive to receiving the notification from the wait process, the media library management application issuing one or more commands that are dependent upon completion of the unmount operation.

2. The method according to claim 1, wherein the media library management application is configured to inhibit commands that are dependent upon completion of the unmount operation until the notification from the wait process is received.

3. The method according to claim 1, wherein the one or more commands include a command to unmount the currently mounted medium.

4. The method according to claim 1, wherein the media library management application starts a timeout process concurrently with the unmount process.

5. The method according to claim 4, wherein the media library management application starts a kill process that terminates the unmount process when the unmount operation has exceeded a predetermined time limit per the timeout process.

6. The method according to claim 1, wherein the wait process is configured to detect completion of the unmount operation.

7. The method according to claim 1, wherein the wait process terminates after the notification is sent.

8. An appliance configured to be coupled between one or more host devices and a media library that includes a plurality of media selectively mountable in one or more drives of the media library, the appliance comprising:

a computer processor;

a memory coupled to the computer processor;

an operating system executing on the computer processor; and

a media library management application executing on the computer processor and communicating with the one or more host devices to enable the one or more host devices access to the media library;

wherein the media library management application is configured to initiate an unmount process to unmount a currently mounted medium of the plurality of media in the media library from a drive in the media library, the currently mounted medium having a currently mounted filesystem;

wherein, responsive to the media library management application initiating the unmount process, the operating system initiates an unmount operation to unmount the currently mounted filesystem;

wherein, until the unmount operation is complete, a wait process running in a monitor thread created by the media library management application and a filesystem process remain pending, the wait process configure to monitor the filesystem process for a change in state;

wherein when the unmount operation is complete, the filesystem process terminates;

wherein, responsive to termination of the filesystem process, the wait process sends a notification to the media library management application; and

wherein, responsive to receiving the notification from the wait process, the media library management application issues one or more commands that are dependent upon completion of the unmount operation.

9. The appliance of claim 8, wherein the media library management application is configured to inhibit commands that are dependent upon completion of the unmount operation until the notification from the wait process is received.

10. The appliance of claim 8, wherein the one or more commands include a command to unmount the currently mounted medium.

11. The appliance of claim 8, wherein the media library management application is configured to start a timeout process concurrently with the unmount process.

12. The appliance of claim 11, wherein the media library management application is configured to start a kill process that terminates the unmount process when the unmount operation has exceeded a predetermined time limit per the timeout process.

13. The appliance of claim 8, wherein the wait process is configured to detect completion of the unmount operation.

14. The appliance of claim 8, wherein the wait process terminates after the notification is sent.

15. A computer program product comprising at least one non-transitory computer readable medium storing instructions translatable by a computer processor of an appliance, the appliance configured to be coupled between one or more host devices and a media library that includes a plurality of media selectively mountable in one or more drives of the media library, the instructions when translated by the computer processor:

initiate an unmount process for a currently mounted medium of the plurality of media in the media library, the currently mounted medium having a currently mounted filesystem;

responsive to the unmount process, initiate an unmount operation to unmount the currently mounted filesystem;

until the unmount operation is complete, continue to run a filesystem process and to run a wait process in a monitor thread, the wait process configured to monitor the filesystem process for a change in state, wherein when the unmount operation is complete, the filesystem process terminates and the wait process terminates after sending out a notification; and

responsive to the notification from the wait process, issue one or more commands that are dependent upon completion of the unmount operation.

16. The computer program product of claim 15, wherein the instructions when translated by the computer processor inhibit commands that are dependent upon completion of the unmount operation until the notification from the wait process is received.

17. The computer program product of claim 15, wherein the one or more commands include a command to unmount the currently mounted medium.

18. The computer program product of claim 15, wherein the instructions when translated by the computer processor start a timeout process concurrently with the unmount process.

19. The computer program product of claim 18, wherein the instructions when translated by the computer processor start a kill process that terminates the unmount process when the unmount operation has exceeded a predetermined time limit per the timeout process.

20. The computer program product of claim 15, wherein the wait process is configured to detect completion of the unmount operation.