Posts

2025 Year-End Summary: Transition from DBA technical operations to providing systematic solutions, expanding into economics and philosophy reading, and deep reflection on AIOps

Analyzing how high-concurrency updates on the same row cause massive row locks and LWLock LockManager waits, verifying through benchmarks that row locks bypassing the fastpath mechanism is the root cause of increased LWLock contention

Starting from the collation mismatch exception, this article dives deep into PostgreSQL collation version management and the principles of operating system libc dependencies.

A deep reading of SIGMOD 2024 Best Industrial Paper PolarDB-MP: a multi-primary cloud-native database based on disaggregated shared memory and RDMA, solving the single-primary write bottleneck

A deep reading of SIGMOD 2025 Best Industrial Paper PolarDB-CXL: introducing CXL disaggregated memory to PolarDB-MP, comparing RDMA architecture and showcasing CXL's advantages in latency and memory fusion

A horizontal comparison of logical replication architectures and their pros and cons across Oracle, MySQL, and PostgreSQL, with an in-depth evaluation of each database's replication philosophy.

Analysis of severely inaccurate n_distinct statistics, deep dive into the Haas-Stokes DISTINCT estimation algorithm in PostgreSQL source code and its estimation bias when sample size is much smaller than total rows

Starting from a query conflict on a static table, this article dives deep into the root causes of standby query conflicts in PostgreSQL and the principles behind XLOG_HEAP2_CLEAN.

Analyzing a case where performance dropped after adding an index: the new index caused the optimizer to choose a different execution path, and the cached generic plan prevented ANALYZE from updating the erroneous cached plan

Analysis of how 8 parameters in the control file are synchronized to the standby via PARAMETER_CHANGE WAL records, and the impact of wal_log_hints primary-standby mismatch on pg_rewind