Scheduled System Maintenance on May 29th, 2015:
IEEE Xplore will be upgraded between 11:00 AM and 10:00 PM EDT. During this time there may be intermittent impact on performance. We apologize for any inconvenience.
By Topic

Dynamic storage fragmentation and file deterioration

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

1 Author(s)
Leung, C.H.C. ; Univ. Coll. of London, UK

As a result of insertions and deletions, a file tends to be cluttered with deleted records which are physically present. These unwanted records cause fragmentation within the file and give rise to additional access overhead because they have to be skipped over during processing. A connection between the dynamic fragmentation characteristics and the pattern of record insertions and deletions over time is presented, and performance degradation is studied in terms of the number of record accesses per reference. Deterioration characteristics are obtained for nonhomogeneous Poisson insertion and general deletion processes. For constant insertion rate, it is found that the deterioration over time is asymptotically linear, with the rate of decline governed by the record deletion rate. An expression for the optimum compaction interval is also given for files subject to a constant insertion rate and an exponentially distributed record lifetime.

Published in:

Software Engineering, IEEE Transactions on  (Volume:SE-12 ,  Issue: 3 )