BUG-6522: grow namespaces lazily

NamespaceStorageSupport is the superclass of StatementContextBase,
hence allocating a default-sized HashMap results in ~75MiB wasted
space. Add lazy expansion to limit the overhead associated with
tracking these.

This patch includes 885bb2cb055b7786b6a44d490499949380750644.

Change-Id: I0825aee92487c94421ef9e505152bbc5fc7383cb
Signed-off-by: Robert Varga <rovarga@cisco.com>
(cherry picked from commit af16d2e800fbad3b91655214498f8737f915c7ac)

diff --git a/yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/NamespaceStorageSupport.java b/yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/NamespaceStorageSupport.java
index c9a9cde76265eb910d9b6cab302a5bc606b59cc9..067cb6fa3b7d9fd662202e0a290abbce40558477 100644 (file)
--- a/yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/NamespaceStorageSupport.java
+++ b/yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/reactor/NamespaceStorageSupport.java
@@ -7,6 +7,7 @@
  */
 package org.opendaylight.yangtools.yang.parser.stmt.reactor;
 
+import com.google.common.collect.ImmutableMap;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -22,7 +23,7 @@ import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.Utils;
 
 abstract class NamespaceStorageSupport implements NamespaceStorageNode {
 
-    private final Map<Class<?>, Map<?,?>> namespaces = new HashMap<>();
+    private Map<Class<?>, Map<?,?>> namespaces = ImmutableMap.of();
 
     @Override
     public abstract NamespaceStorageNode getParentNamespaceStorage();
@@ -111,6 +112,10 @@ abstract class NamespaceStorageSupport implements NamespaceStorageNode {
         if (localNamespace == null) {
             checkLocalNamespaceAllowed(type);
             localNamespace = new HashMap<>(1);
+
+            if (namespaces.isEmpty()) {
+                namespaces = new HashMap<>(1);
+            }
             namespaces.put(type, localNamespace);
         }
         localNamespace.put(key,value);