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57e810c852
We want to exclude repair with tablet migrations to avoid races between repair reads and writes with replica movement. Repair is not prepared to handle topology transitions in the middle. One reason why it's not safe is that repair may successfully write to a leaving replica post streaming phase and consider all replicas to be repaired, but in fact they are not, the new replica would not be repaired. Other kinds of races could result in repair failures. If repair writes to a leaving replica which was already cleaned up, such writes will fail, causing repair to fail. Excluding works by keeping effective_replication_map_ptr in a version which doesn't have table's tablets in transitions. That prevents later transitions from starting because topology coordinator's barrier will wait for that erm before moving to a stage later than allow_write_both_read_old, so before any requests start using the new topology. Also, if transitions are already running, repair waits for them to finish. A blocked tablet migration (e.g. due to down node) will block repair, whereas before it would fail. Once admin resolves the cause of blocked migration, repair will continue. Fixes #17658. Fixes #18561. Closes scylladb/scylladb#18641 * github.com:scylladb/scylladb: test: pylib: Do not block async reactor while removing directories repair: Exclude tablet migrations with tablet repair repair_service: Propagate topology_state_machine to repair_service main, storage_service: Move topology_state_machine outside storage_service storage_srvice, toplogy: Extract topology_state_machine::await_quiesced() tablet_scheduler: Make disabling of balancing interrupt shuffle mode tablet_scheduler: Log whether balancing is considered as enabled