diff --git a/doc/src/sgml/ref/pg_waldump.sgml b/doc/src/sgml/ref/pg_waldump.sgml
index e5f9637847e..4592d6016a5 100644
--- a/doc/src/sgml/ref/pg_waldump.sgml
+++ b/doc/src/sgml/ref/pg_waldump.sgml
@@ -283,7 +283,7 @@ PostgreSQL documentation
        </para>
        <para>
         The full page images are saved with the following file name format:
-        <literal><replaceable>LSN</replaceable>.<replaceable>RELTABLESPACE</replaceable>.<replaceable>DATOID</replaceable>.<replaceable>RELNODE</replaceable>.<replaceable>BLKNO</replaceable><replaceable>FORK</replaceable></literal>
+        <literal><replaceable>TIMELINE</replaceable>-<replaceable>LSN</replaceable>.<replaceable>RELTABLESPACE</replaceable>.<replaceable>DATOID</replaceable>.<replaceable>RELNODE</replaceable>.<replaceable>BLKNO</replaceable><replaceable>FORK</replaceable></literal>
 
         The file names are composed of the following parts:
         <informaltable>
@@ -296,6 +296,13 @@ PostgreSQL documentation
           </thead>
 
           <tbody>
+           <row>
+            <entry>TIMELINE</entry>
+            <entry>The timeline of the WAL segment file where the record
+             is located formatted as one 8-character hexadecimal number
+             <literal>%08X</literal></entry>
+           </row>
+
            <row>
             <entry>LSN</entry>
             <entry>The <acronym>LSN</acronym> of the record with this image,
diff --git a/src/bin/pg_waldump/pg_waldump.c b/src/bin/pg_waldump/pg_waldump.c
index c6d3ae63445..96845e1a1ae 100644
--- a/src/bin/pg_waldump/pg_waldump.c
+++ b/src/bin/pg_waldump/pg_waldump.c
@@ -518,7 +518,8 @@ XLogRecordSaveFPWs(XLogReaderState *record, const char *savepath)
 		else
 			pg_fatal("invalid fork number: %u", fork);
 
-		snprintf(filename, MAXPGPATH, "%s/%08X-%08X.%u.%u.%u.%u%s", savepath,
+		snprintf(filename, MAXPGPATH, "%s/%08X-%08X-%08X.%u.%u.%u.%u%s", savepath,
+				 record->seg.ws_tli,
 				 LSN_FORMAT_ARGS(record->ReadRecPtr),
 				 rnode.spcOid, rnode.dbOid, rnode.relNumber, blk, forkname);
 
diff --git a/src/bin/pg_waldump/t/002_save_fullpage.pl b/src/bin/pg_waldump/t/002_save_fullpage.pl
index 831ffdefefd..f0725805f21 100644
--- a/src/bin/pg_waldump/t/002_save_fullpage.pl
+++ b/src/bin/pg_waldump/t/002_save_fullpage.pl
@@ -79,15 +79,16 @@ $node->command_ok(
 	'pg_waldump with --save-fullpage runs');
 
 # This regexp will match filenames formatted as:
-# XXXXXXXX-XXXXXXXX.DBOID.TLOID.NODEOID.dd_fork with the components being:
-# - WAL LSN in hex format,
-# - Tablespace OID (0 for global)
+# TLI-LSNh-LSNl.TBLSPCOID.DBOID.NODEOID.dd_fork with the components being:
+# - Timeline ID in hex format.
+# - WAL LSN in hex format, as two 8-character numbers.
+# - Tablespace OID (0 for global).
 # - Database OID.
 # - Relfilenode.
 # - Block number.
 # - Fork this block came from (vm, init, fsm, or main).
 my $file_re =
-  qr/^([0-9A-F]{8})-([0-9A-F]{8})[.][0-9]+[.][0-9]+[.][0-9]+[.][0-9]+(?:_vm|_init|_fsm|_main)?$/;
+  qr/^[0-9A-F]{8}-([0-9A-F]{8})-([0-9A-F]{8})[.][0-9]+[.][0-9]+[.][0-9]+[.][0-9]+(?:_vm|_init|_fsm|_main)?$/;
 
 my $file_count = 0;