On WAL Redundancy in Postgres
summary
Explains redundancy in PostgreSQL WAL (write-ahead log) files and shows that WAL data compresses highly, indicating excess redundancy. Demonstrates how changing physical cluster parameters can significantly improve local write efficiency and replication throughput, while also warning that some changes can cause serious incidents.
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chapters (10)
- 0:00Introduction
- 1:53WAL purpose and history
- 6:11WAL invariant in Postgres
- 9:42Full page writes impact
- 12:54WAL structure and segments
- 17:44Recovery and replication
- 19:51WAL compression optimization
- 26:52Full record compression
- 33:16Summary and outlook
- 33:38Q&A
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