More documentation for node count limit

Change-Id: I6b35ee3ee6b9f8a84e997bbf09aa72c807caf71e

diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index 2fa0c57..98b4589 100644 (file)
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -3224,8 +3224,13 @@ $wgMaxTocLevel = 999;
 $wgMaxPPNodeCount = 1000000;
 
 /**
- * A complexity limit on template expansion: the maximum number of nodes 
- * generated by Preprocessor::preprocessToObj()
+ * A complexity limit on template expansion: the maximum number of elements
+ * generated by Preprocessor::preprocessToObj(). This allows you to limit the
+ * amount of memory used by the Preprocessor_DOM node cache: testing indicates
+ * that each element uses about 160 bytes of memory on a 64-bit processor, so
+ * this default corresponds to about 155 MB.
+ *
+ * When the limit is exceeded, an exception is thrown.
  */
 $wgMaxGeneratedPPNodeCount = 1000000;