Managing your Tuple Graveyard - Chelsea Dole

Learn how to identify, measure, and mitigate tuple bloating in PostgreSQL databases, including effective autovacuum configuration, vacuuming strategies, and best practices for system management to prevent performance issues.

Key takeaways

Tweet-level tuple bloating is considered acceptable, up to 25% dead tuples.
pgStatTuple shows a percentage of live tuples alongside other values.
Autovacuum config can be modified to be more aggressive, but it’s not recommended.
Blob-like data can lead to high disk usage, especially with large tables.
Tuple bloating can cause space to be wasted, potentially exceeding disk limits.
The pgRepack module can be used to reclaim unused space.
Autovacuum cost delay can be used to throttle vacuuming based on available resources.
Bloat is often the root cause of other issues, such as high disk usage and poor performance.
Tuple bloating can be measured using queries like pg_stat_tuple.
Vacuuming can be forced using pg_stat_tuple and autovacuum.
It’s recommended to run analyze on large tables to get accurate results.
Tuple bloating can be mitigated by increasing autovacuum interval and size.
Isolation and resource management are key to managing tuple bloating.
Overly aggressive autovacuum settings can lead to unnecessary scans and performance issues.
Managing tuple bloating requires a holistic view of the system, including user behavior and database layout.
Triggering vacuuming only when necessary can help improve performance.

Managing your Tuple Graveyard - Chelsea Dole

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