Deferred Reference Counters for Copy-On-Write B-trees

Initial work on copy-on-write friendly b-trees has shown how to efficiently use reference counters to build file-systems that support snapshots and clones. However, unassisted, the disk-access pattern when accessing the ref-counters is random. This is not a good match to contemporary hard disk technology, which favors sequential workloads.

This work attempts to improve the access pattern by deferring and batching ref-count updates.

By: Ohad Rodeh

Published in: RJ10464 REVISED in 2010


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