[CASSANDRA-5972] Reduce the amount of data to be transferred during repair

• Type: Improvement
• Status: Open
• Priority: Low
• Resolution: Unresolved
• Component/s: Consistency/Repair
• Labels: remove-reopen
• Assignee: Unassigned
• Reporter: Jacek Lewandowski
• Created: 03/Sep/13 08:57
• Updated: 16/Apr/19 09:32

Description

Currently, when a validator finds a token range different in n replicas, data streams are initiated simultaneously between each possible pair of these n nodes, in both directions. It yields n*(n-1) data stream in total.

It can be done in a sequence - Replica[1] -> R[2], R[2] -> R[3], ... , R[n-1] -> R[n]. After this process, the data in R[n] are up to date. Then, we continue: R[n] -> R[1], R[1] -> R[2], ... , R[n-2] -> R[n-1]. The active repair is done after 2*(n-1) data transfers performed sequentially in 2*(n-1) steps.

Issue Links

• duplicates: CASSANDRA-3200 Repair: compare all trees together (for a given range/cf) instead of by pair in isolation