1 files changed, 37 insertions, 9 deletions

diff --git a/src/backend/replication/pgoutput/pgoutput.c b/src/backend/replication/pgoutput/pgoutput.c
index c8f5c7f8641..e178bd77abc 100644
--- a/src/backend/replication/pgoutput/pgoutput.c
+++ b/src/backend/replication/pgoutput/pgoutput.c
@@ -82,6 +82,13 @@ static void pgoutput_stream_prepare_txn(LogicalDecodingContext *ctx,
 static bool publications_valid;
 static bool in_streaming;
 
+/*
+ * Private memory context for publication data, created in
+ * PGOutputData->context when starting pgoutput, and set to NULL when its
+ * parent context is reset via a dedicated MemoryContextCallback.
+ */
+static MemoryContext pubctx = NULL;
+
 static List *LoadPublications(List *pubnames);
 static void publication_invalidation_cb(Datum arg, int cacheid,
 										uint32 hashvalue);
@@ -386,6 +393,15 @@ parse_output_parameters(List *options, PGOutputData *data)
 }
 
 /*
+ * Callback of PGOutputData->context in charge of cleaning pubctx.
+ */
+static void
+pgoutput_pubctx_reset_callback(void *arg)
+{
+	pubctx = NULL;
+}
+
+/*
  * Initialize this plugin
  */
 static void
@@ -394,6 +410,7 @@ pgoutput_startup(LogicalDecodingContext *ctx, OutputPluginOptions *opt,
 {
 	PGOutputData *data = palloc0(sizeof(PGOutputData));
 	static bool publication_callback_registered = false;
+	MemoryContextCallback *mcallback;
 
 	/* Create our memory context for private allocations. */
 	data->context = AllocSetContextCreate(ctx->context,
@@ -404,6 +421,15 @@ pgoutput_startup(LogicalDecodingContext *ctx, OutputPluginOptions *opt,
 										   "logical replication cache context",
 										   ALLOCSET_DEFAULT_SIZES);
 
+	Assert(pubctx == NULL);
+	pubctx = AllocSetContextCreate(ctx->context,
+								   "logical replication publication list context",
+								   ALLOCSET_SMALL_SIZES);
+
+	mcallback = palloc0(sizeof(MemoryContextCallback));
+	mcallback->func = pgoutput_pubctx_reset_callback;
+	MemoryContextRegisterResetCallback(ctx->context, mcallback);
+
 	ctx->output_plugin_private = data;
 
 	/* This plugin uses binary protocol. */
@@ -1728,9 +1754,9 @@ pgoutput_origin_filter(LogicalDecodingContext *ctx,
 /*
  * Shutdown the output plugin.
  *
- * Note, we don't need to clean the data->context and data->cachectx as
- * they are child contexts of the ctx->context so they will be cleaned up by
- * logical decoding machinery.
+ * Note, we don't need to clean the data->context, data->cachectx and pubctx
+ * as they are child contexts of the ctx->context so they will be cleaned up
+ * by logical decoding machinery.
  */
 static void
 pgoutput_shutdown(LogicalDecodingContext *ctx)
@@ -1740,6 +1766,9 @@ pgoutput_shutdown(LogicalDecodingContext *ctx)
 		hash_destroy(RelationSyncCache);
 		RelationSyncCache = NULL;
 	}
+
+	/* Better safe than sorry */
+	pubctx = NULL;
 }
 
 /*
@@ -2040,12 +2069,11 @@ get_rel_sync_entry(PGOutputData *data, Relation relation)
 		/* Reload publications if needed before use. */
 		if (!publications_valid)
 		{
-			oldctx = MemoryContextSwitchTo(CacheMemoryContext);
-			if (data->publications)
-			{
-				list_free_deep(data->publications);
-				data->publications = NIL;
-			}
+			Assert(pubctx);
+
+			MemoryContextReset(pubctx);
+			oldctx = MemoryContextSwitchTo(pubctx);
+
 			data->publications = LoadPublications(data->publication_names);
 			MemoryContextSwitchTo(oldctx);
 			publications_valid = true;