Shashikant Shakya

Vacuuming Enhancements in PostgreSQL 18: Faster, Smarter, More Predictable

local CEST (Livestream 4)

PostgreSQL 18 delivers one of the most significant sets of VACUUM and ANALYZE improvements in years, making maintenance faster, more predictable, and easier to tune. This session highlights the key changes and explains how they automatically alleviate common pain points in real-world workloads, backed by field experience.

We’ll cover:

• Asynchronous I/O (AIO): Overlaps reads with processing to reduce heap-scan delays and speed up VACUUM.
• Dynamic autovacuum scaling: Adjust autovacuum_max_workers on the fly without restarts for elastic maintenance.
• Earlier autovacuum triggers: Use autovacuum_vacuum_max_threshold and hard caps to prevent bloat on large tables.
• Eager freezing: Shortens future anti-wraparound VACUUMs automatically.
• Explicit tail shrinking: Reclaims unused space at the end of tables without blocking operations.
• Recursive VACUUM/ANALYZE: Handles inheritance-based partitions seamlessly and avoids redundant ANALYZE for declarative parents.
• Improved observability: Real-time cost-delay attribution (track_cost_delay_timing), per-backend I/O/WAL stats, and byte-level I/O metrics for proactive tuning.