Do not try to fetch the last key when we do not have to

jeltz · jeltz · commit 1338ceb1377b · 2025-08-19T12:04:30.000+02:00
This is likely a leftover from when the logic for unencrypted keys
was different from the one for real encryption keys.
diff --git a/contrib/pg_tde/src/access/pg_tde_xlog_smgr.c b/contrib/pg_tde/src/access/pg_tde_xlog_smgr.c
@@ -368,19 +368,16 @@ tdeheap_xlog_seg_write(int fd, const void *buf, size_t count, off_t offset,
 	lastKeyUsable = (writeKeyLoc.lsn != 0);
 	afterWriteKey = wal_location_cmp(writeKeyLoc, loc) <= 0;
 
-	if (EncryptionKey.type != WAL_KEY_TYPE_INVALID && !lastKeyUsable && afterWriteKey)
+	if (EncryptionKey.type != WAL_KEY_TYPE_INVALID && !lastKeyUsable && afterWriteKey && !crashRecovery)
 	{
 		WALKeyCacheRec *last_key = pg_tde_get_last_wal_key();
 
-		if (!crashRecovery)
+		if (last_key == NULL || last_key->start.lsn < loc.lsn)
 		{
-			if (last_key == NULL || last_key->start.lsn < loc.lsn)
-			{
-				pg_tde_wal_last_key_set_location(loc);
-				EncryptionKey.wal_start = loc;
-				TDEXLogSetEncKeyLocation(EncryptionKey.wal_start);
-				lastKeyUsable = true;
-			}
+			pg_tde_wal_last_key_set_location(loc);
+			EncryptionKey.wal_start = loc;
+			TDEXLogSetEncKeyLocation(EncryptionKey.wal_start);
+			lastKeyUsable = true;
 		}
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -368,19 +368,16 @@ tdeheap_xlog_seg_write(int fd, const void *buf, size_t count, off_t offset,`
`368`	`368`	`lastKeyUsable = (writeKeyLoc.lsn != 0);`
`369`	`369`	`afterWriteKey = wal_location_cmp(writeKeyLoc, loc) <= 0;`
`370`	`370`
`371`		`- if (EncryptionKey.type != WAL_KEY_TYPE_INVALID && !lastKeyUsable && afterWriteKey)`
	`371`	`+ if (EncryptionKey.type != WAL_KEY_TYPE_INVALID && !lastKeyUsable && afterWriteKey && !crashRecovery)`
`372`	`372`	`{`
`373`	`373`	`WALKeyCacheRec *last_key = pg_tde_get_last_wal_key();`
`374`	`374`
`375`		`- if (!crashRecovery)`
	`375`	`+ if (last_key == NULL \|\| last_key->start.lsn < loc.lsn)`
`376`	`376`	`{`
`377`		`- if (last_key == NULL \|\| last_key->start.lsn < loc.lsn)`
`378`		`- {`
`379`		`- pg_tde_wal_last_key_set_location(loc);`
`380`		`- EncryptionKey.wal_start = loc;`
`381`		`- TDEXLogSetEncKeyLocation(EncryptionKey.wal_start);`
`382`		`- lastKeyUsable = true;`
`383`		`- }`
	`377`	`+ pg_tde_wal_last_key_set_location(loc);`
	`378`	`+ EncryptionKey.wal_start = loc;`
	`379`	`+ TDEXLogSetEncKeyLocation(EncryptionKey.wal_start);`
	`380`	`+ lastKeyUsable = true;`
`384`	`381`	`}`
`385`	`382`	`}`
`386`	`383`