Hi all, We want to start a discussion thread for KIP-1303: Deprioritize Tiered Storage Followers In Leader Election.
The adopted KIP-1023 introduced an optimization allowing followers to skip replicating data already in remote storage, dramatically reducing ISR join time. However, as noted in KIP-1023, this creates a risk: if such a follower becomes leader, it may need to serve consumer requests from remote storage, impacting performance. This KIP proposes to mitigate this risk by preferring replicas with more local data (lower localLogStartOffset) during leader election. Key changes include: 1) New config leader.election.prefer.early.local.log.start.offset to enable the feature 2) New config leader.election.local.log.start.offset.threshold to avoid leader churn from minor retention timing differences 3) Extending FetchRequest and AlterPartition to propagate localLogStartOffset from followers → leader → controller The full KIP is available here: https://cwiki.apache.org/confluence/display/KAFKA/KIP-1303%3A+Deprioritize+Tiered+Storage+Followers+In+Leader+Election Thanks, Tom
