diff --git a/addons/base_import/models/base_import.py b/addons/base_import/models/base_import.py
index 35d5692e95b..4e4945fd37c 100644
--- a/addons/base_import/models/base_import.py
+++ b/addons/base_import/models/base_import.py
@@ -885,6 +885,8 @@ class Import(models.TransientModel):
         try:
             if dryrun:
                 self._cr.execute('ROLLBACK TO SAVEPOINT import')
+                # cancel all changes done to the registry/ormcache
+                self.pool.reset_changes()
             else:
                 self._cr.execute('RELEASE SAVEPOINT import')
         except psycopg2.InternalError:
diff --git a/odoo/addons/base/models/ir_config_parameter.py b/odoo/addons/base/models/ir_config_parameter.py
index eed10daadd8..b7f2356e803 100644
--- a/odoo/addons/base/models/ir_config_parameter.py
+++ b/odoo/addons/base/models/ir_config_parameter.py
@@ -83,7 +83,8 @@ class IrConfigParameter(models.Model):
         if param:
             old = param.value
             if value is not False and value is not None:
-                param.write({'value': value})
+                if str(value) != old:
+                    param.write({'value': value})
             else:
                 param.unlink()
             return old
diff --git a/odoo/models.py b/odoo/models.py
index 1af6cd9c173..b2aab1d5f36 100644
--- a/odoo/models.py
+++ b/odoo/models.py
@@ -846,7 +846,6 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
         ids = []
         messages = []
         ModelData = self.env['ir.model.data']
-        ModelData.clear_caches()
 
         # list of (xid, vals, info) for records to be created in batch
         batch = []
@@ -928,6 +927,8 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
         if any(message['type'] == 'error' for message in messages):
             cr.execute('ROLLBACK TO SAVEPOINT model_load')
             ids = False
+            # cancel all changes done to the registry/ormcache
+            self.pool.reset_changes()
 
         return {'ids': ids, 'messages': messages}
 
diff --git a/odoo/modules/loading.py b/odoo/modules/loading.py
index bc95e1c461d..5fb56887948 100644
--- a/odoo/modules/loading.py
+++ b/odoo/modules/loading.py
@@ -151,8 +151,6 @@ def load_module_graph(cr, graph, status=None, perform_checks=True,
     module_count = len(graph)
     _logger.info('loading %d modules...', module_count)
 
-    registry.clear_caches()
-
     # register, instantiate and initialize models for each modules
     t0 = time.time()
     t0_sql = odoo.sql_db.sql_counter
@@ -278,9 +276,6 @@ def load_module_graph(cr, graph, status=None, perform_checks=True,
 
     _logger.log(25, "%s modules loaded in %.2fs, %s queries", len(graph), time.time() - t0, odoo.sql_db.sql_counter - t0_sql)
 
-    registry.clear_caches()
-
-
     return loaded_modules, processed_modules
 
 def _check_module_names(cr, module_names):