diff --git a/libs/ardour/ardour/luaproc.h b/libs/ardour/ardour/luaproc.h
index 38d4961480..06478503f5 100644
--- a/libs/ardour/ardour/luaproc.h
+++ b/libs/ardour/ardour/luaproc.h
@@ -30,7 +30,6 @@
 #include <vector>
 #include <string>
 
-#define USE_TLSF
 #ifdef USE_TLSF
 #  include "pbd/tlsf.h"
 #else
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 11c4ad2e41..0addab67bc 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -60,11 +60,15 @@
 #include "pbd/event_loop.h"
 #include "pbd/file_archive.h"
 #include "pbd/rcu.h"
-#include "pbd/reallocpool.h"
 #include "pbd/statefuldestructible.h"
 #include "pbd/signals.h"
 #include "pbd/undo.h"
 
+#ifdef USE_TLSF
+#  include "pbd/tlsf.h"
+#else
+#  include "pbd/reallocpool.h"
+#endif
 #include "lua/luastate.h"
 
 #include "temporal/range.h"
@@ -1677,7 +1681,11 @@ private:
 	bool              pending_abort;
 	bool              pending_auto_loop;
 
+#ifdef USE_TLSF
+	PBD::TLSF _mempool;
+#else
 	PBD::ReallocPool _mempool;
+#endif
 	LuaState lua;
 	mutable Glib::Threads::Mutex lua_lock;
 	luabridge::LuaRef * _lua_run;
diff --git a/libs/ardour/luabindings.cc b/libs/ardour/luabindings.cc
index ad54522587..5fe47f0671 100644
--- a/libs/ardour/luabindings.cc
+++ b/libs/ardour/luabindings.cc
@@ -3456,7 +3456,7 @@ ARDOUR::Session::luabindings_session_rt (lua_State* L)
 {
 	/* declaration need to be in this file due to Windows CLASSKEYS */
 	luabridge::getGlobalNamespace (L)
-		.beginNamespace ("Ardour")
+		.beginNamespace ("ARDOUR")
 		.beginClass <Session> ("Session")
 		/* thse are private to Session */
 		.addFunction ("rt_set_controls", &Session::rt_set_controls)
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 9c80d3bde8..604e704cd1 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -260,8 +260,14 @@ Session::Session (AudioEngine &eng,
 	, _last_roll_or_reversal_location (0)
 	, _last_record_location (0)
 	, pending_auto_loop (false)
-	, _mempool ("Session", 3145728)
+	, _mempool ("Session", 4194304)
+#ifdef USE_TLSF
+	, lua (lua_newstate (&PBD::TLSF::lalloc, &_mempool))
+#elif defined USE_MALLOC
+	, lua (lua_newstate (true, true))
+#else
 	, lua (lua_newstate (&PBD::ReallocPool::lalloc, &_mempool))
+#endif
 	, _lua_run (0)
 	, _lua_add (0)
 	, _lua_del (0)
diff --git a/libs/ardour/wscript b/libs/ardour/wscript
index 3a24f0b731..12f223b865 100644
--- a/libs/ardour/wscript
+++ b/libs/ardour/wscript
@@ -325,6 +325,8 @@ def configure(conf):
         if conf.is_defined ('HAVE_LV2_1_10_0'):
             conf.define ('LV2_EXTENDED', 1)
 
+    conf.define ('USE_TLSF', 1)
+
     #autowaf.check_pkg(conf, 'soundtouch', uselib_store='SOUNDTOUCH',
     #                  atleast_version='1.8.0', mandatory=False)
     autowaf.check_pkg(conf, 'cppunit', uselib_store='CPPUNIT',
diff --git a/wscript b/wscript
index 88c3efdbf1..055401e009 100644
--- a/wscript
+++ b/wscript
@@ -1191,10 +1191,10 @@ def configure(conf):
                         fragment = "#include <dlfcn.h>\n int main(void) { dlopen (\"\", 0); return 0;}\n",
                         lib='dl', uselib_store='DL', execute = False)
 
-    conf.check_cxx(fragment = "#include <boost/version.hpp>\n#if !defined (BOOST_VERSION) || BOOST_VERSION < 105600\n#error boost >= 1.56 is not available\n#endif\nint main(void) { return 0; }\n",
+    conf.check_cxx(fragment = "#include <boost/version.hpp>\n#if !defined (BOOST_VERSION) || BOOST_VERSION < 106800\n#error boost >= 1.68 is not available\n#endif\nint main(void) { return 0; }\n",
               execute = False,
               mandatory = True,
-              msg = 'Checking for boost library >= 1.56')
+              msg = 'Checking for boost library >= 1.68')
 
     if re.search ("linux", sys.platform) is not None and Options.options.dist_target != 'mingw':
         autowaf.check_pkg(conf, 'alsa', uselib_store='ALSA')