Storage replication systems and methods

Patent metadata

Field	Value
Publication number	US-9235595-B2
Application number	US-63891209-A
Country	US
Kind code	B2
Filing date	Dec 15, 2009
Priority date	Oct 2, 2009
Publication date	Jan 12, 2016
Grant date	Jan 12, 2016

Abstract

Systems and methods for information storage replication are presented. In one embodiment, a namespace conversion process is performed. Node information regarding a file systems operation change is received. A changed node to pathname object conversion process is performed. An unchanged node to pathname object conversion process is performed. In one exemplary implementation, the changed node to pathname object conversion process and the unchanged node to pathname object conversion process utilize data structures that return the object indications and parent node indications. An object indication is inserted in a pathname.

First claim

What is claimed is:

1. A method of efficient conversion of information associated with a node during file replication comprising:
receiving node information regarding an operation change of a particular node in a file system;
determining that the received node information is associated with the particular node of the file system identified in a file change log;
in the event the received node information associated with the particular node identified in the file change log corresponds to namespace changes of the particular node between session checkpoints, performing a changed node to pathname object conversion process on the received node information using a name space conversion component, wherein said changed node to pathname object conversion process utilizes a name space alteration tracking data structure to determine a changed object indicator;
in the event the received node information associated with the particular node identified in the file change log does not correspond to namespace changes of the particular node between session checkpoints, performing an unchanged node to pathname object conversion process on the received node information using the name space conversion component, wherein said unchanged node to pathname object conversion process utilizes a longest path tracking data structure to determine an unchanged object indicator;
inserting the changed or unchanged object indicator in a pathname of the particular node based upon results of at least one of said changed node to pathname object conversion process and said unchanged node to pathname object conversion process;
forwarding said pathname with said inserted object indicator to a target storage resource;
receiving a call to roll back one or more changes between session checkpoints for the particular node using a roll back interface and a marker uniquely identifying an entry in the file change log; and
restarting conversion of the node information associated with the particular node during file replication from a point indicated by the marker.

2. The file replication method of claim 1 wherein said changed node to pathname object conversion process and said unchanged node to pathname object conversion process utilize data structures that return said changed and unchanged object indicators.

3. The file replication method of claim 1 wherein said changed node to pathname object conversion process and said unchanged node to pathname object conversion process utilize data structures that return parent node indicators.

4. The file replication method of claim 1 wherein the name space alteration tracking data structure maps a node indicator associated with a namespace change to a parent node indicator and an object name.

5. The file replication method of claim 4 wherein said name space alteration tracking data structure includes a hash table.

6. The file replication method of claim 1 wherein said longest path tracking data structure is a prefix tree.

7. The file replication method of claim 1 further comprising returning a parent object node indicator as an input to said changed node pathname object conversion process.

8. The file replication method of claim 1 further comprising returning a parent object node indicator as an input to said unchanged node to pathname object conversion process.

9. An article of manufacture including a non-transitory computer readable storage medium having instructions stored thereon that if executed by a computing device cause the computing device to perform a storage image replication, the instructions comprising:
an image freezing module that manages frozen snapshots of a source file system at session checkpoints;
a file change log examination module that retrieves entries in a file change log, wherein said entries correspond to namespace changes of node information of a particular node of the source file system between said session checkpoints;
a namespace conversion module that:
converts node indications corresponding to said entries from said file change log to pathname indications in the event said entries correspond to the namespace changes of the node information of the particular node between said session checkpoints,
utilizes a name space alteration tracking data structure to determine a changed object indicator of the particular node in the event said entries correspond to the namespace changes of the particular node between said session checkpoints;
utilizes a longest path tracking data structure to determine an unchanged object indicator of the particular node in the event said entries do not correspond to the namespace changes of the particular node between said session checkpoints; and
inserting the changed or unchanged object indicator in said pathname indications of the particular node based upon results of at least one of said changed node to pathname object conversion process and said unchanged node to pathname object conversion process;

a filter module that filters unnecessary operations;
a delta file data retrieval module that retrieves changes in file data of the particular node of the said source file system between said session checkpoints; and
a delta operation module for:
forwarding said pathname indications with said inserted object indicator and said changes in said file data to a target storage resource;
receiving a call to roll back one or more of said changes of the particular node between session checkpoints using a roll back interface and a marker uniquely identifying an entry in the file change log; and
restarting conversion of the node information associated with the particular node during file replication from a point indicated by the marker.

10. The computer readable medium of claim 9 wherein said namespace conversion module comprises:
a node indication receiving module that determines if a node indication is received;
a changed node to pathname object conversion module that performs a changed node to pathname object conversion process;
an unchanged node to pathname object conversion module that performs an unchanged node to pathname object conversion process; and
an object indication insertion module for inserting an object name in a pathname.

11. The computer readable medium of claim 10 wherein said changed node to pathname object conversion module obtains an object name associated with a node involved corresponding namespace change.

12. The computer readable medium of claim 10 wherein said unchanged node to pathname object conversion module obtains an object name associated with a node not involved in a corresponding namespace change.

13. The computer readable medium of claim 10 wherein said node indication includes a unique inode number.

14. The computer readable medium of claim 10 wherein said changed node to pathname object conversion module and said unchanged node to pathname object conversion module utilize data structures that return said object name.

15. The computer readable medium of claim 10 wherein said changed node to pathname object conversion module recursively processes parent node indicators.

16. The computer readable medium of claim 10 wherein said unchanged node to pathname object conversion module recursively processes parent node indicators.

17. An information storage replication system comprising:
at least one computer processor; and
at least one memory, coupled to the at least one computer processor, having instructions stored therein which, when executed by the at least one computer processor, causes the at least one computer processor to perform operations comprising:
storing, in

Assignees

• Wang Feng
• Zhang Pu Paul
• Agrawal Mukund
• Kumar Sumit
• Symantec Corp

Inventors

• Wang Feng
• Zhang Pu Paul
• Agrawal Mukund
• Kumar Sumit

Classifications

• G06F16/1787 Primary

  Details of non-transparently synchronising file systems · CPC title

• G06F16/1734

  Details of monitoring file system events, e.g. by the use of hooks, filter drivers, logs · CPC title

• G06F16/184

  implemented as replicated file system · CPC title

• G06F16/166

  File name conversion · CPC title

• G06F17/30123

  Physics · mapped topic