container: reduce the number of fetched iterator items (#3558)

Author: cthulhu-rider

CHANGELOG.md

@@ -9,6 +9,7 @@ Changelog for NeoFS Node
 - Send on closed channel panic in node's new epoch handler (#3529)
 - Tomstoned objects revival not working (#3542)
 - Negative logic object counters in metabase (#3555)
+- Inability to list 2K+ containers via API (#3558)
 
 ### Changed
 - Stream payload without buffering to reduce memory usage in CLI `Get/Put` operations (#3535)

pkg/morph/client/container/client.go

@@ -41,8 +41,10 @@ const (
 
 	// iteratorPrefetchNumber is a number of stack items to prefetch in the
 	// first call of iterator-based methods. neo-go's stack elements default
-	// limit is 2048, make it less a little.
-	iteratorPrefetchNumber = 2000
+	// limit is 2048, but JSON output is then limited to 128K, given that
+	// each item has ~30 bytes overhead for type/value structure using large
+	// values is dangerous here.
+	iteratorPrefetchNumber = 512
 )
 
 var (