Re: Logical Replication of sequences

Hi Vignesh,

Some review comments for patch v20250422-0003.

======
src/backend/replication/logical/syncutils.c

1.
+/*
+ * Exit routine for synchronization worker.
+ */
+pg_noreturn void
+SyncFinishWorker(void)

Why does this have the pg_noreturn annotation? None of the other void
functions do.

~~~

2.
+bool
+FetchRelationStates(bool *started_tx)

All the functions in the sync utils.c are named like Syncxxx, so for
consistency, why not name this one also?
e.g. /FetchRelationStates/SyncFetchRelationStates/

======
src/backend/replication/logical/tablesync.c

3.
-static bool
-wait_for_relation_state_change(Oid relid, char expected_state)
+bool
+WaitForRelationStateChange(Oid relid, char expected_state)
{
char state;
~

3a.
Why isn't this static, like before?

~

3b.
If it is *only* for tables and nothing else, shouldn't it be static
and have a function name like 'wait_for_table_state_change' (not
_relation_)?
OTOH, if there is potential for this to be used for sequences in
future, then it should be in the syncutils.c module with a name like
'SyncWaitForRelationStateChange'.

======
src/include/replication/worker_internal.h

4.
@@ -250,6 +252,7 @@ extern void logicalrep_worker_stop(Oid subid, Oid relid);
extern void logicalrep_pa_worker_stop(ParallelApplyWorkerInfo *winfo);
extern void logicalrep_worker_wakeup(Oid subid, Oid relid);
extern void logicalrep_worker_wakeup_ptr(LogicalRepWorker *worker);
+pg_noreturn extern void SyncFinishWorker(void);

extern int logicalrep_sync_worker_count(Oid subid);

@@ -259,9 +262,13 @@ extern void
ReplicationOriginNameForLogicalRep(Oid suboid, Oid relid,
extern bool AllTablesyncsReady(void);
extern void UpdateTwoPhaseState(Oid suboid, char new_state);

-extern void process_syncing_tables(XLogRecPtr current_lsn);
-extern void invalidate_syncing_table_states(Datum arg, int cacheid,
- uint32 hashvalue);
+extern bool FetchRelationStates(bool *started_tx);
+extern bool WaitForRelationStateChange(Oid relid, char expected_state);
+extern void ProcessSyncingTablesForSync(XLogRecPtr current_lsn);
+extern void ProcessSyncingTablesForApply(XLogRecPtr current_lsn);
+extern void SyncProcessRelations(XLogRecPtr current_lsn);
+extern void SyncInvalidateRelationStates(Datum arg, int cacheid,
+ uint32 hashvalue);

~

4a.
Why does SyncFinishWorker have the pg_noreturn annotation? None of the
other void functions do.

~

4b.
I felt that all the SyncXXX functions exposed from syncutils.c should
be grouped together, and maybe even with a comment like /* from
syncutils.c */

======
Kind Regards,
Peter Smith.
Fujitsu Australia