Improve errors related to incorrect TLI on checkpoint record replay

WAL replay would cause a hard crash if the timeline expected by a
XLOG_END_OF_RECOVERY, a XLOG_CHECKPOINT_ONLINE, or a
XLOG_CHECKPOINT_SHUTDOWN record is not the same as the timeline being
replayed, using the same error message for all three of them.  This
commit changes those error messages to use different wordings, adapted
to each record type, which is useful when it comes to the debugging of
an issue in this area.

Author: Amul Sul
Reviewed-by: Nathan Bossart, Robert Haas
Discussion: https://postgr.es/m/CAAJ_b97i1ZerYC_xW6o_AiDSW5n+sGi8k91Yc8KS8bKWKxjqwQ@mail.gmail.com

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 58922f7edea83b573d1ff24c15751425f6f92982..dfe2a0bcce984b6be4e05ddda493c20d1fd1b4e9 100644 (file)
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -10421,7 +10421,7 @@ xlog_redo(XLogReaderState *record)
                 */
                if (checkPoint.ThisTimeLineID != replayTLI)
                        ereport(PANIC,
-                                       (errmsg("unexpected timeline ID %u (should be %u) in checkpoint record",
+                                       (errmsg("unexpected timeline ID %u (should be %u) in shutdown checkpoint record",
                                                        checkPoint.ThisTimeLineID, replayTLI)));
 
                RecoveryRestartPoint(&checkPoint, record);
@@ -10477,7 +10477,7 @@ xlog_redo(XLogReaderState *record)
                /* TLI should not change in an on-line checkpoint */
                if (checkPoint.ThisTimeLineID != replayTLI)
                        ereport(PANIC,
-                                       (errmsg("unexpected timeline ID %u (should be %u) in checkpoint record",
+                                       (errmsg("unexpected timeline ID %u (should be %u) in online checkpoint record",
                                                        checkPoint.ThisTimeLineID, replayTLI)));
 
                RecoveryRestartPoint(&checkPoint, record);
@@ -10507,7 +10507,7 @@ xlog_redo(XLogReaderState *record)
                 */
                if (xlrec.ThisTimeLineID != replayTLI)
                        ereport(PANIC,
-                                       (errmsg("unexpected timeline ID %u (should be %u) in checkpoint record",
+                                       (errmsg("unexpected timeline ID %u (should be %u) in end-of-recovery record",
                                                        xlrec.ThisTimeLineID, replayTLI)));
        }
        else if (info == XLOG_NOOP)