Log file optimization in a client/server computing system

Patent 5740432 Issued on April 14, 1998. Estimated Expiration Date:

May 28, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Partitioned log-structured file system and methods for operating the same Patent #: 5537588
Issued on: 07/16/1996
Inventor: Engelmann, et al.

Inventor

Mastors, Robert

Application

No. 654330 filed on 05/28/1996

US Classes:

707/202, Recoverability714/20Plural recovery data sets containing set interrelation data (e.g., time values or log record numbers)

Examiners

Primary: Kulik, Paul V.

Attorney, Agent or Firm

Foreign Patent References

WO 95 24685 A WO. 09/13/1995

International Class

G06F 017/30

Abstract

In a client/server computing system, a method and apparatus for efficiently storing entries in a log file during disconnected client operations. An encoder utilizes a log file and a write file table for logging the write operations performed by the client during disconnected operations. The logging method employed by the encoding module logs in the log file only writes associated for different files. The encoding module tracks the status of the entries in the log file with a write file table containing the most recent sequence number associated with a file entry of the log file. Upon reconnection of the client to the server, a decoding module replays the events in the correct chronological order by transferring the file data modified during the period of disconnection in the order dictated by the write file table. A deferred write list is accessed by the decoding module for temporary storage any write operations whose replay should be delayed to preserve the relative order of events.

Other References

Michael N. Nelsou, "Generic Support for Caching and Disconnected Operation", Workstation Operating Systems, 1993, pp. 61-65
M. Satyanarayanan et al., "On the Vbiquity of Logging in Distributed File Systems", Workstation Operating Systems, 1992, pp. 122-125
James J. Kistler et al., "Disconneted Operatin in the Coda File System", ACM Transactions on Computer Systems, vol. 10, No. 1, Feb. 1992, pp. 3-25
"Disconnected Operation", http://www.cs.sunysb.ed/~cchang/paper/g.20html, date unkown
Puneet Kuman, "Coping with Conflicts in an Optimistically Replicated File System", 1990 Workshop on Management of Replicated Data, IEEE, 1990, pp. 60-64
James J. Kistler, "Increasing File System Availability through Second-Class Replication", 1990 Workshop on Management of Replicated Data, IEEE, 1990, pp. 65-69
ACM Transactions on Computer Systems, vol. 10, No. 1, 1 Feb. 1992, pp. 3-25, Kistler J., "Disconnected Operation in the Coda File System"
Proceedings of the Usenix Mobile and Location-Independent Computing Symposium, 2 Aug. 1993, pp. 1-10, Huston L., "Disconnected Operation for AFS