diff --git a/doc/src/sgml/brin.sgml b/doc/src/sgml/brin.sgml
index 23c0e05ed6..f02e061bc1 100644
--- a/doc/src/sgml/brin.sgml
+++ b/doc/src/sgml/brin.sgml
@@ -86,6 +86,18 @@
    representation because the existing values have changed.
   </para>
 
+  <para>
+   When autosummarization is enabled, each time a page range is filled a
+   request is sent to autovacuum for it to execute a targeted summarization
+   for that range, to be fulfilled at the end of the next worker run on the
+   same database.  If the request queue is full, the request is not recorded
+   and a message is sent to the server log:
+<screen>
+LOG:  request for BRIN range summarization for index "brin_wi_idx" page 128 was not recorded
+</screen>
+   When this happens, the range will be summarized normally during the next
+   regular vacuum of the table.
+  </para>
  </sect2>
 </sect1>
 
diff --git a/src/backend/access/brin/brin.c b/src/backend/access/brin/brin.c
index 68b3371665..0e5849efdc 100644
--- a/src/backend/access/brin/brin.c
+++ b/src/backend/access/brin/brin.c
@@ -187,9 +187,19 @@ brininsert(Relation idxRel, Datum *values, bool *nulls,
 				brinGetTupleForHeapBlock(revmap, lastPageRange, &buf, &off,
 										 NULL, BUFFER_LOCK_SHARE, NULL);
 			if (!lastPageTuple)
-				AutoVacuumRequestWork(AVW_BRINSummarizeRange,
-									  RelationGetRelid(idxRel),
-									  lastPageRange);
+			{
+				bool	recorded;
+
+				recorded = AutoVacuumRequestWork(AVW_BRINSummarizeRange,
+												 RelationGetRelid(idxRel),
+												 lastPageRange);
+				if (!recorded)
+					ereport(LOG,
+							(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+							 errmsg("request for BRIN range summarization for index \"%s\" page %u was not recorded",
+									RelationGetRelationName(idxRel),
+									lastPageRange)));
+			}
 			else
 				LockBuffer(buf, BUFFER_LOCK_UNLOCK);
 		}
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 639bd716b1..c4bc09ea81 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -3227,12 +3227,14 @@ AutoVacuumingActive(void)
 
 /*
  * Request one work item to the next autovacuum run processing our database.
+ * Return false if the request can't be recorded.
  */
-void
+bool
 AutoVacuumRequestWork(AutoVacuumWorkItemType type, Oid relationId,
 					  BlockNumber blkno)
 {
 	int			i;
+	bool		result = false;
 
 	LWLockAcquire(AutovacuumLock, LW_EXCLUSIVE);
 
@@ -3252,12 +3254,15 @@ AutoVacuumRequestWork(AutoVacuumWorkItemType type, Oid relationId,
 		workitem->avw_database = MyDatabaseId;
 		workitem->avw_relation = relationId;
 		workitem->avw_blockNumber = blkno;
+		result = true;
 
 		/* done */
 		break;
 	}
 
 	LWLockRelease(AutovacuumLock);
+
+	return result;
 }
 
 /*
diff --git a/src/include/postmaster/autovacuum.h b/src/include/postmaster/autovacuum.h
index 18cff540b7..96752caed8 100644
--- a/src/include/postmaster/autovacuum.h
+++ b/src/include/postmaster/autovacuum.h
@@ -71,7 +71,7 @@ extern void AutovacuumWorkerIAm(void);
 extern void AutovacuumLauncherIAm(void);
 #endif
 
-extern void AutoVacuumRequestWork(AutoVacuumWorkItemType type,
+extern bool AutoVacuumRequestWork(AutoVacuumWorkItemType type,
 					  Oid relationId, BlockNumber blkno);
 
 /* shared memory stuff */