diff --git a/ChangeLog b/ChangeLog
index b26f87d5..cd79b63e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2009-03-28  Tatsuhiro Tsujikawa  <t-tujikawa@users.sourceforge.net>
+
+	Run
+	DefaultBtMessageDispatcher::checkRequestSlotAndDoNecessaryThing()
+	in every 1 sec. The timeout of RequestSlot is 60s by default and
+	it doesn't need to be called every time when
+	DefaultBtInteractive::doInteractionProcessing() is called.	
+	* src/DefaultBtInteractive.cc
+	* src/DefaultBtInteractive.h
+
 2009-03-25  Tatsuhiro Tsujikawa  <t-tujikawa@users.sourceforge.net>
 
 	Documented 'falloc' in man page.
diff --git a/src/DefaultBtInteractive.cc b/src/DefaultBtInteractive.cc
index 1c37c27e..ef91f64b 100644
--- a/src/DefaultBtInteractive.cc
+++ b/src/DefaultBtInteractive.cc
@@ -438,8 +438,10 @@ void DefaultBtInteractive::doInteractionProcessing() {
 
   detectMessageFlooding();
 
-  dispatcher->checkRequestSlotAndDoNecessaryThing();
-
+  if(_perSecCheckPoint.elapsed(1)) {
+    _perSecCheckPoint.reset();
+    dispatcher->checkRequestSlotAndDoNecessaryThing();
+  }
   checkHave();
 
   sendKeepAlive();
diff --git a/src/DefaultBtInteractive.h b/src/DefaultBtInteractive.h
index d364404f..dd3a79bb 100644
--- a/src/DefaultBtInteractive.h
+++ b/src/DefaultBtInteractive.h
@@ -123,6 +123,7 @@ private:
   FloodingStat floodingStat;
   Time inactiveCheckPoint;
   Time _pexCheckPoint;
+  Time _perSecCheckPoint;
   time_t keepAliveInterval;
   bool _utPexEnabled;
   bool _dhtEnabled;