diff --git a/src/Db/Db.py b/src/Db/Db.py
index 22a10516..9f372fc3 100644
--- a/src/Db/Db.py
+++ b/src/Db/Db.py
@@ -5,7 +5,10 @@ import logging
 import re
 import os
 import atexit
+import threading
 import sys
+import weakref
+import errno
 
 import gevent
 
@@ -71,6 +74,7 @@ class Db(object):
         self.schema["version"] = self.schema.get("version", 1)
         self.conn = None
         self.cur = None
+        self.cursors = weakref.WeakSet()
         self.id = next_db_id
         next_db_id += 1
         self.progress_sleeping = False
@@ -121,10 +125,16 @@ class Db(object):
                 "Connected to %s in %.3fs (opened: %s, sqlite version: %s)..." %
                 (self.db_path, time.time() - s, len(opened_dbs), sqlite3.version)
             )
+            self.log.debug("Connect by thread: %s" % threading.current_thread().ident)
             self.log.debug("Connect called by %s" % Debug.formatStack())
         finally:
             self.connect_lock.release()
 
+    def getConn(self):
+        if not self.conn:
+            self.connect()
+        return self.conn
+
     def progress(self, *args, **kwargs):
         self.progress_sleeping = True
         time.sleep(0.001)
@@ -199,6 +209,7 @@ class Db(object):
     def close(self, reason="Unknown"):
         if not self.conn:
             return False
+        self.connect_lock.acquire()
         s = time.time()
         if self.delayed_queue:
             self.processDelayed()
@@ -207,10 +218,19 @@ class Db(object):
         self.need_commit = False
         self.commit("Closing: %s" % reason)
         self.log.debug("Close called by %s" % Debug.formatStack())
+        for i in range(10):
+            if len(self.cursors) == 0:
+                break
+            self.log.debug("Pending cursors: %s" % len(self.cursors))
+            time.sleep(0.1 * i)
+        if len(self.cursors):
+            self.log.debug("Killing cursors: %s" % len(self.cursors))
+            self.conn.interrupt()
+
         if self.cur:
             self.cur.close()
         if self.conn:
-            self.conn.close()
+            ThreadPool.main_loop.call(self.conn.close)
         self.conn = None
         self.cur = None
         self.log.debug("%s closed (reason: %s) in %.3fs, opened: %s" % (self.db_path, reason, time.time() - s, len(opened_dbs)))