Tuning Concurrent Performance is Hard.

PostgreSQL 14.{0,1,2,3} 行 CREATE INDEX CONCURRENTLY 有機會靜悄悄地炒，成個 Index 會失蹤！

如果有朋友用緊 14.{0,1,2,3} 記得睇下自己有冇用 concurrently，如有的話，好大機會你有啲 query 冇用緊 index 繼而產生 performance issue，暫時只要用番 CREATE INDEX 就可以 hotfix 到。

事源係追塑到 PostgreSQL 14 想提升 concurrent performance，結果出咗 regression，喺 14.4 已經 revert 咗 code change （見圖 ）

Tuning concurrent performance is hard.

Code changes: https://github.com/postgres/postgres/commit/e28bb885196916b0a3d898ae4f2be0e38108d81b

Index 失蹤 bug report: https://www.postgresql.org/message-id/17485-396609c6925b982d%40postgresql.org