I created a patch corresponding FPW.
Fujii's patch (ver 9) is based.
Manage own FPW in shared-memory (on master)
* startup and walwriter process update it. startup initializes it
after REDO. walwriter updates it when started or received SIGHUP.
Insert WAL including a value of current FPW (on master)
* In the the same timing as update, they insert WAL (is named
XLOG_FPW_CHANGE). XLOG_FPW_CHANGE has a value of the changed FPW.
* When it creates CHECKPOINT, it adds a value of current FPW to the
CHECKPOINT WAL.
Manage master's FPW in local-memory in startup (on standby)
* It takes a value of the master's FPW by reading XLOG_FPW_CHANGE at
REDO.
Check when pg_start_backup/pg_stop_backup (on standby)
* It checks to use these two value.
* master's FPW at latest CHECKPOINT
* current master's FPW by XLOG_FPW_CHANGE
Regards.
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Jun Ishizuka
NTT Software Corporation
TEL：045-317-7018
E-Mail: ishizuka.jun@po.ntts.co.jp
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