Postgresql hard
What is the most severe operational consequence of an abandoned 'Logical Replication Slot' remaining active on a primary producer node?
- A The memory allocated to the WAL sender process will leak until the primary node crashes from OOM.
- B The primary will hoard all WAL files indefinitely, eventually exhausting all available disk space.
- C The logical decoder will automatically down-scale the shared buffer pool to prioritize network I/O.
- D The replica will be permanently banned from the cluster until the slot is manually re-authorized.
Answer: B. The primary will hoard all WAL files indefinitely, eventually exhausting all available disk space.
A replication slot tells the primary: 'Don't delete these WAL files; I still need to read them.' If the subscriber dies and the slot isn't dropped, the `pg_wal` directory will grow until the disk is 100% full, crashing the database.
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