Add config option for max commit iterations

lib/config.coffee

@@ -67,7 +67,8 @@ options = {
   MAX_CONCURRENT_REQUESTS : {type : 'int', default: 20},
   DATETIME_MILLISECONDS : {type: 'bool', default: true},
   BOOLEAN_LITERAL : {type: 'bool', default: true},
-  CONNECTION_REQUEST_ALLOW_BASIC_AUTH: {type: 'bool', default: false}
+  CONNECTION_REQUEST_ALLOW_BASIC_AUTH: {type: 'bool', default: false},
+  MAX_COMMIT_ITERATIONS : {type : 'int', default: 32},
 
   # XML configuration
   XML_RECOVER : {type : 'bool', default : false},

lib/session.coffee

@@ -29,7 +29,8 @@ InstanceSet = require './instance-set'
 defaultProvisions = require './default-provisions'
 gpnHeuristic = require './gpn-heuristic'
 
-MAX_ITERATIONS = 64
+# Multiply by two because every iteration is two phases: read and update
+MAX_ITERATIONS = config.get('MAX_COMMIT_ITERATIONS') * 2
 
 provisionsCache = new WeakMap()
 virtualParametersCache = new WeakMap()