closes #6105, reduce to 50K

git-svn-id: file:///svn/toku/tokudb@53683 c7de825b-a66e-492c-adef-691d508d4ae1

locktree/locktree.h

@@ -327,7 +327,7 @@ class locktree {
     // if the system goes single threaded, it ought to be pretty quick
     // for 100 transactions to go by, so we won't have to wait long before
     // we start doing the single txind optimzation again.
-    static const int STO_BUFFER_MAX_SIZE = 1 * 1024 * 1024;
+    static const int STO_BUFFER_MAX_SIZE = 50 * 1024;
     static const int STO_SCORE_THRESHOLD = 100;
     int m_sto_score;