Method for updating a block using record-level locks by committi

Boots – shoes – and leggings

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

395650, 395425, 3642468, 36424291, 364269, 364DIG1, 3642821, G06F 1208

Patent

active

053554779

ABSTRACT:
A Virtual Storage Access Management (VSAM) technique for maintaining data integrity of the record-level shared data in a multiprocessor system environment without the concurrency loss associated with locking at the data Control Interval (CI) or block level. Two or more concurrent processes can update different records within the same VSAM data CI using only a record-level lock. This feature relies upon multiple private data CI copies, Shared External Storage (SES), cache cross-invalidation, and a conditional writing operation. A first process updates a private copy of a data CI containing the target record from SES, logs the changes, and writes the changed data CI back to the SES conditioned upon no update having been made to the same block data CI by a second process in the interim. If a second process has indeed updated the same data CI in the interim, the first process recycles by obtaining the most recent data CI copy from SES, combining it with the first process update log entries and attempting to again conditionally write the modified data CI to SES. This process of logging updates and spinning on an intervening update by another process preserves serialization by record-level locking alone.

REFERENCES:
patent: 4604694 (1986-08-01), Hough
patent: 4716528 (1987-12-01), Crus et al.
patent: 4775955 (1988-10-01), Liu
patent: 4853843 (1989-08-01), Ecklund
patent: 4961134 (1990-10-01), Crus et al.
patent: 5043876 (1991-08-01), Terry
patent: 5060144 (1991-10-01), Sipple et al.
patent: 5151988 (1992-09-01), Yamagishi
patent: 5155824 (1992-10-01), Edenfield et al.
patent: 5163148 (1992-11-01), Walls
patent: 5210848 (1993-05-01), Liu
MVS/EsA VSAM Administration Guide SC 26-4518, International Business Machines, Inc., Armonk, N.Y. (Version 3 Release 1, Jul. 1991).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method for updating a block using record-level locks by committi does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for updating a block using record-level locks by committi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for updating a block using record-level locks by committi will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1665635

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.