Synchronizing data recovery logs for snapshot-based data recovery in a distributed deduplication system

A method of providing a cluster-wide synchronization point for use as a data recovery snapshot in a cluster file system having similarity groups generating log data, comprising:

• filling a recovery log of a plurality of recovery logs each organized into a plurality of uniform log data units with log data generated by a corresponding similarity group, wherein the recovery logs are filled at different rates;
• syncing, when a log data unit is filled, corresponding log data to disk storage;
• truncating the recovery log at the filled log data unit to define a log tail;
• appending new log data to a log head comprising a first empty log data unit after any partially filled log data units;
• marking, with a timestamp, each filled log data unit with a time corresponding to when it is synced to the disk storage;
• identifying an earliest timestamp of the marked filled log data units;
• and
• matching the earliest timestamp with a snapshot backup of the cluster file system taken at a same corresponding time for use as a backup image for restoring the cluster file system.

A system providing a cluster-wide synchronization point for use as a data recovery snapshot in a cluster file system, comprising:

• an interface first accessing recovery logs for a plurality of similarity groups of the cluster file system, wherein each similarity group maintains a respective recovery log, and wherein the recovery logs are loaded with log data at different rates, and second accessing snapshot backups of the cluster file system taken on a periodic basis;
• a recovery log processor filling a recovery log of a plurality of recovery logs each organized into a plurality of uniform log data units with log data generated by a corresponding similarity group, wherein the recovery logs are filled at different rates, truncating the recovery log at the filled log data unit to define a log tail, and appending new log data to a log head comprising a first empty log data unit after any partially filled log data units;
• a synchronization component determining an earliest time of storage to disk of log data in the recovery logs;
• and
• a data protection component utilizing a snapshot backup taken at a time corresponding to the earliest time as a backup image to restore the system in the event of a crash of the cluster file system or corruption of one or more of the recovery logs.