PostgreSQL: TOAST, Backup and Hash Table Reliability Fixes
Three reliability fixes address stale TOAST index state after concurrent reindex, torn control-file reads in base backups, and oversized hash tables, alongside overflow checks for integer aggregates and a view-deparsing correction.
Duration: PT2M28S
Episode overview
This episode is a short developer briefing from PostgreSQL.
It explains recent repository work in plain language.
- Show: PostgreSQL
- Published: 2026-10-28T13:04:07Z
- Audio duration: PT2M28S
Transcript excerpt
This excerpt keeps the crawler page concise. Listen to the episode or use the RSS feed for the full update.
Good morning, it's October 28th, 2026, and this is your PostgreSQL developer briefing.
The throughline today is hardening against rare but severe failures — stale caches, torn reads, and runaway memory requests.
First, concurrent operations and backups. Commit 2741727 fixes stale index flags kept in memory for TOAST indexes after a concurrent reindex. An affected backend would keep marking the new index as not ready, skip writing new TOAST chunks there, and then fail reads with a missing chunk error once the old index was…
Second, executor and SQL correctness. Commit 34d52e6 reintroduces a memory-based cap on hash table buckets, after reports that poor estimates could request up to four billion buckets and exhaust memory. The change trades possible table growth for safety. Commit 903ce58 adds overflow detection to sum and average over…
Finally, code hygiene: two cleanups remove an unused predicate-locking check and a duplicated interface list in the predicate locking code.
What's next: most of these reliability fixes are queued for backpatching, so expect them in upcoming stable releases, and if you've seen missing TOAST chunk errors after a concurrent reindex, plan a TOAST index…
Nearby episodes from PostgreSQL
- Weekly Recap - Executor Correctness and Data Safety
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- Planner Correctness and Crash Fixes
- Planner Correctness and JSON Error Handling
- Query Tracking Overhaul and Data Integrity Fixes
- Planner Correctness and Crash Safety Fixes
- Weekly Recap - Planner Correctness and Data Safety Fixes
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