When to use an aggressive scrub

Change from using a normal scrub by enabling the Aggressive Scrub checkbox when configuring a FileFly scrub policy to reclaim Swarm storage space.

As of FileFly version 3.1 all scrub operations are by default aggressive so there is no checkbox to enable.

Normal

Cleans up old versions and deleted objects

Normal scrub removes the files/stubs deleted from the primary storage from Swarm.

Both scrub types remove from Swarm any old versions of files, keeping in Swarm the current version of the file existing on the primary storage.

Aggressive

Cleans up old versions and deleted objects

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Cleans up demigrated objects

Aggressive scrub removes the files/stubs deleted from the primary storage and those demigrated (transferred from Swarm back to the primary storage) from Swarm.

This is a strategy to use when it is critical to maximize space recovery in Swarm Storage. Aggressive scrubbing does this at the price of the ability to run quick remigrates (remigration of previously unmodified demigrated files; quick remigration occurs without data transfer between the primary storage and Swarm).

Best practice

When using aggressive scrubbing, to also maximize performance benefits from quick-remigration, schedule the migration / quick-remigration policies to run more frequently than the grace period.