PostgreSQL problem analysis 1: the timeline is inconsistent

First, question: requested timeline% u does not contain minimum recovery point% X on timeline% u

The location of the log in the code is as follows:

StartupXLOG: if (! XLogRecPtrIsInvalid (ControlFile- > minRecoveryPoint) & & tliOfPointInHistory (ControlFile- > minRecoveryPoint-1, expectedTLEs)! = ControlFile- > minRecoveryPointTLI) ereport (FATAL, (errmsg ("requested timeline% u does not contain minimum recovery point% X minRecoveryPointTLI% X on timeline% u", recoveryTargetTLI, (uint32) (ControlFile- > minRecoveryPoint > > 32) (uint32) ControlFile- > minRecoveryPoint, ControlFile- > minRecoveryPointTLI)

2. Analysis

What is the value of recoveryTargetTLI?

1. During the start-up and recovery process, the change value is as follows:

StartupXLOG:... If (ControlFile- > minRecoveryPointTLI > ControlFile- > checkPointCopy.ThisTimeLineID) recoveryTargetTLI = ControlFile- > minRecoveryPointTLI; else recoveryTargetTLI = ControlFile- > checkPointCopy.ThisTimeLineID; readRecoveryCommandFile ();-- for (item = head; item; item = item- > next) {|... | else if (strcmp (item- > name, "recovery_target_timeline") = = 0) {| rtliGiven = true | | if (strcmp (item- > value, "latest") = = 0) | rtli = 0; | else | rtli = (TimeLineID) strtoul (item- > value, NULL, 0); |} |. |} | | if (rtliGiven) {| if (rtli) {| recoveryTargetTLI = rtli | | | recoveryTargetIsLatest = false; |} else {| recoveryTargetTLI = findNewestTimeLine (recoveryTargetTLI); | recoveryTargetIsLatest = true; |} |--} |

First, the timeline ControlFile- > minRecoveryPointTLI of the minimum recovery point recorded by the pg_control file is compared with the timeline ControlFile- > checkPointCopy.ThisTimeLineID of the checkpoint recorded by the pg_control file, and the recoveryTargetTLI takes a larger value between the two.

ReadRecoveryCommandFile then reads the recovery.cnf file, and if it is a host, there is no recovery.cnf file. The value of recovery_target_timeline in the recovery.cnf file specifies the timeline to which it is restored. If it is latest, the timeline rtli is 0 otherwise it is the specified value; if rtli is the specified value, then recoveryTargetTLI is the specified value, otherwise, starting from the recoveryTargetTLI value obtained in the first step, see if there is a history file for it, and find the maximum timeline for the history file for which recoveryTargetTLI is the timeline.