diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 0c3e2b0..3a1b1f7 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -167,6 +167,9 @@ static const struct
 	}
 };
 
+/* Number of consecutive blocks to allocate per parallel seq scan batch */
+#define PARALLEL_SEQSCAN_PAGES_PER_BATCH 10
+
 /* Get the LOCKMODE for a given MultiXactStatus */
 #define LOCKMODE_from_mxstatus(status) \
 			(tupleLockExtraInfo[TUPLOCK_from_mxstatus((status))].hwlock)
@@ -298,6 +301,9 @@ initscan(HeapScanDesc scan, ScanKey key, bool keep_startblock)
 	scan->rs_cbuf = InvalidBuffer;
 	scan->rs_cblock = InvalidBlockNumber;
 
+	scan->rs_batchcurrblock = InvalidBlockNumber;
+	scan->rs_batchlastblock = InvalidBlockNumber;
+
 	/* page-at-a-time fields are always invalid when not rs_inited */
 
 	/*
@@ -1676,6 +1682,18 @@ heap_parallelscan_nextpage(HeapScanDesc scan)
 	BlockNumber report_page = InvalidBlockNumber;
 	ParallelHeapScanDesc parallel_scan;
 
+	/*
+	 * First attempt read the next block from a sequence of blocks previously
+	 * assigned to this worker.  If only a single block is only ever assigned
+	 * then we'll never find a block here.
+	 */
+	if (scan->rs_batchcurrblock != InvalidBlockNumber &&
+		scan->rs_batchcurrblock < scan->rs_batchlastblock)
+	{
+		scan->rs_batchcurrblock++;
+		return scan->rs_batchcurrblock;
+	}
+
 	Assert(scan->rs_parallel);
 	parallel_scan = scan->rs_parallel;
 
@@ -1712,18 +1730,45 @@ retry:
 	 * The current block number is the next one that needs to be scanned,
 	 * unless it's InvalidBlockNumber already, in which case there are no more
 	 * blocks to scan.  After remembering the current value, we must advance
-	 * it so that the next call to this function returns the next block to be
-	 * scanned.
+	 * it so that it's set to the next block which needs to be scanned.
+	 *
+	 * To try to reduce contention on the mutex we allocate a range of blocks
+	 * to each worker so that they only must acquire a lock once they've
+	 * processed all of the blocks in their allocated range.
 	 */
 	page = parallel_scan->phs_cblock;
 	if (page != InvalidBlockNumber)
 	{
-		parallel_scan->phs_cblock++;
+		scan->rs_batchcurrblock = parallel_scan->phs_cblock;
+		scan->rs_batchlastblock = scan->rs_batchcurrblock +
+									PARALLEL_SEQSCAN_PAGES_PER_BATCH - 1;
+
+		parallel_scan->phs_cblock += PARALLEL_SEQSCAN_PAGES_PER_BATCH;
+
 		if (parallel_scan->phs_cblock >= scan->rs_nblocks)
-			parallel_scan->phs_cblock = 0;
-		if (parallel_scan->phs_cblock == parallel_scan->phs_startblock)
+		{
+			/*
+			 * We've stepped off the end of the range of blocks to scan, we'll
+			 * need to shorten this batch to just the remaining blocks.
+			 */
+			scan->rs_batchlastblock = scan->rs_nblocks - 1;
+
+			/* If we started the scan at block 0 then we're done */
+			if (parallel_scan->phs_startblock == 0)
+			{
+				parallel_scan->phs_cblock = InvalidBlockNumber;
+				report_page = 0;
+			}
+			else
+				parallel_scan->phs_cblock = 0;
+		}
+
+		if (parallel_scan->phs_startblock > 0 &&
+			scan->rs_batchcurrblock < parallel_scan->phs_startblock &&
+			scan->rs_batchlastblock >= parallel_scan->phs_startblock - 1)
 		{
 			parallel_scan->phs_cblock = InvalidBlockNumber;
+			scan->rs_batchlastblock = parallel_scan->phs_startblock - 1;
 			report_page = parallel_scan->phs_startblock;
 		}
 	}
diff --git a/src/include/access/relscan.h b/src/include/access/relscan.h
index 3fc726d..5be3ef6 100644
--- a/src/include/access/relscan.h
+++ b/src/include/access/relscan.h
@@ -71,6 +71,10 @@ typedef struct HeapScanDescData
 	/* NB: if rs_cbuf is not InvalidBuffer, we hold a pin on that buffer */
 	ParallelHeapScanDesc rs_parallel;	/* parallel scan information */
 
+	/* Used to allocate a range of blocks for a parallel worker to scan */
+	BlockNumber rs_batchcurrblock; /* current parallel block in batch */
+	BlockNumber rs_batchlastblock; /* final parallel block in batch */
+
 	/* these fields only used in page-at-a-time mode and for bitmap scans */
 	int			rs_cindex;		/* current tuple's index in vistuples */
 	int			rs_ntuples;		/* number of visible tuples on page */