Synonyms
PiT copy; Snapshot
Definition
A point-in-time copy is a copy of original data as it appeared at a point in time. In a conventional backup operation, users often create a PiT Copy, while an application is in quiescing, to make the PiT Copy a consistent copy of original data.
Key Points
There are two popular implementation techniques for creating PiT Copies inside a storage system: split mirror and copy on write.
Split mirror is a technique for replicating the original data at a point in time. In some implementations, a storage system replicates the original data, and when users create the PiT Copy, a storage system splits the replication. Copy on Write (CoW) is a technique for capturing data changes to storage and creating a PiT Copy after specifying the point in time. In some implementations, when users create the PiT Copy, a storage system creates its image with both the original data and the modified data.
Techniques for creating PiT Copies have a trade-off between occupied...
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsRecommended Reading
Alain Azagury, et al. Point-in-time copy: yesterday, today, and tomorrow. In: Proceedings of the IEEE Symposium Conference on Mass Storage Systems and Technologies; 2002.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Section Editor information
Rights and permissions
Copyright information
© 2018 Springer Science+Business Media, LLC, part of Springer Nature
About this entry
Cite this entry
Fujimoto, K. (2018). Point-in-Time Copy. In: Liu, L., Özsu, M.T. (eds) Encyclopedia of Database Systems. Springer, New York, NY. https://doi.org/10.1007/978-1-4614-8265-9_1339
Download citation
DOI: https://doi.org/10.1007/978-1-4614-8265-9_1339
Published:
Publisher Name: Springer, New York, NY
Print ISBN: 978-1-4614-8266-6
Online ISBN: 978-1-4614-8265-9
eBook Packages: Computer ScienceReference Module Computer Science and Engineering