Shulou(Shulou.com)06/01 Report--

The log source will be switched directly in XLOG_FROM_ARCHIVE- > XLOG_FROM_STREAM- > XLOG_FROM_ARCHIVE. If there is an error in the reading process, it will switch to another log source. However, in the actual execution process, XLOG_FROM_ARCHIVE will be read to XLOG_FROM_PG_WAL after an error, but the variables of the log source will not be changed. This requires attention.

Static intXLogFileReadAnyTLI (XLogSegNo segno, int emode, int source) {if (expectedTLEs) tles = expectedTLEs; else tles = readTimeLineHistory (recoveryTargetTLI) / * 1. When WaitForWALToBecomeAvailable is called, when source is XLOG_FROM_ARCHIVE, XLOG_FROM_ANY 2 and XLOG_FROM_ANY will be used, and xlog will be read from the archive first. If open fails, XLOG_FROM_PG_WAL 3 will be used. External log source variables do not switch * / foreach (cell, tles) {TimeLineID tli = ((TimeLineHistoryEntry *) lfirst (cell))-> tli If (tli < curFileTLI) break; / * don't bother looking at too-old TLIs * / if (source = = XLOG_FROM_ANY | | source = = XLOG_FROM_ARCHIVE) {fd = XLogFileRead (segno, emode, tli,XLOG_FROM_ARCHIVE, true) If (fd! =-1) {if (! expectedTLEs) expectedTLEs = tles; return fd }} if (source = = XLOG_FROM_ANY | | source = = XLOG_FROM_PG_WAL) {fd = XLogFileRead (segno, emode, tli, XLOG_FROM_PG_WAL, true) If (fd! =-1) {if (! expectedTLEs) expectedTLEs = tles; return fd;} return-1;}

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