MogDB / openGauss 中如何执行和观察检查点（CheckPoint）

在 MogDB / openGauss 中，可以通过手工执行 checkpoint 命令，触发数据库的检查点执行。

omm@e044904eb372:~$ sh login.sh 
gsql ((MogDB 5.0.9 build 191cef4e) compiled at 2024-10-28 09:53:59 commit 0 last mr 1804 )
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.

MogDB=>checkpoint;
CHECKPOINT

同时在 data/pg_log 目录下的 postgresql 日志中，可以看到数据库的执行过程记录：

2025-07-16 06:59:35.012 [BACKEND] LOG:  will do full checkpoint, need flush 178570 pages.
2025-07-16 06:59:35.014 [SLRU] LOG:  remove old segments(<0) under pg_csnlog
2025-07-16 06:59:35.015 [BACKEND] LOG:  truncate CSN log oldestXact 61140, next xid 98890
2025-07-16 06:59:38.509 [DBL_WRT] LOG:  [batch flush] DW truncate end: file_head[dwn 2975, start 23824], total_pages 0
2025-07-16 06:59:38.513 [BACKEND] LOG:  slotname: wal2json, dummy: 0, restartlsn: 0/5AC4078
2025-07-16 06:59:38.514 [BACKEND] LOG:  CreateCheckPoint PrintCkpXctlControlFile: [checkPoint] oldCkpLoc:20/3AA2FB28, oldRedo:20/38DA2C30, newCkpLoc:20/3AA2FCC8, newRedo:20/3AA2FC48, preCkpLoc:20/38DA2B10
2025-07-16 06:59:38.514[BACKEND] LOG:  will update control file (create checkpoint), shutdown:0
2025-07-16 06:59:38.516 [BACKEND] LOG:  attempting to remove WAL segments older than log file 000000010000000000000003

成功执行的检查点会被记录在控制文件中。