diff --git a/include/trrep/client_context.hpp b/include/trrep/client_context.hpp
index 0c6d880..a0afb8e 100644
--- a/include/trrep/client_context.hpp
+++ b/include/trrep/client_context.hpp
@@ -99,7 +99,9 @@ namespace trrep
             /*! Generates write sets for replication by the provider. */
             m_replicating,
             /*! Applies write sets from the provider. */
-            m_applier
+            m_applier,
+            /*! Client is in total order isolation mode */
+            m_toi
         };
 
         /*!
@@ -345,6 +347,7 @@ namespace trrep
                                             const trrep::data&);
         friend class client_context_switch;
         friend class client_applier_mode;
+        friend class client_toi_mode;
         friend class transaction_context;
 
         /*!
@@ -450,12 +453,12 @@ namespace trrep
         /*!
          * Enter debug synchronization point.
          */
-        virtual void debug_sync(const std::string&) = 0;
+        virtual void debug_sync(const char*) = 0;
 
         /*!
          *
          */
-        virtual void debug_suicide(const std::string&) = 0;
+        virtual void debug_suicide(const char*) = 0;
 
         /*!
          * Notify the implementation about an error.
@@ -526,6 +529,27 @@ namespace trrep
         trrep::client_context& client_;
         enum trrep::client_context::mode orig_mode_;
     };
+
+    class client_toi_mode
+    {
+    public:
+        client_toi_mode(trrep::client_context& client)
+            : client_(client)
+            , orig_mode_(client.mode_)
+        {
+            client_.mode_ = trrep::client_context::m_toi;
+        }
+        ~client_toi_mode()
+        {
+            assert(client_.mode == trrep::client_context::m_toi);
+            client_.mode_ = orig_mode_;
+        }
+    private:
+        trrep::client_context& client_;
+        enum trrep::client_context::mode orig_mode_;
+    };
+
+
 }
 
 #endif // TRREP_CLIENT_CONTEXT_HPP
diff --git a/include/trrep/server_context.hpp b/include/trrep/server_context.hpp
index cdc12a3..e06b013 100644
--- a/include/trrep/server_context.hpp
+++ b/include/trrep/server_context.hpp
@@ -225,34 +225,31 @@ namespace trrep
                     bool bootstrap);
 
         int disconnect();
-        /*!
-         * Virtual method which will be called when the server
-         * has been joined to the cluster. Must be provided by
-         * the implementation.
-         *
-         * \todo Document overriding.
-         */
-        virtual void on_connect();
 
         /*!
-         * Virtual method which will be called when a view
+         * A method which will be called when the server
+         * has been joined to the cluster
+         */
+        void on_connect();
+
+        /*!
+         * A method which will be called when a view
          * notification event has been delivered by the
          * provider.
          *
-         * \todo Document overriding.
-         *
          * \params view trrep::view object which holds the new view
          *         information.
          */
-        virtual void on_view(const trrep::view& view);
+        void on_view(const trrep::view& view);
 
         /*!
-         * Virtual method which will be called when the server
+         * A method which will be called when the server
          * has been synchronized with the cluster.
          *
-         * \todo Document overriding.
+         * This will have a side effect of changing the Server Context
+         * state to s_synced.
          */
-        virtual void on_sync();
+        void on_sync();
 
         /*!
          * Wait until server reaches given state.
@@ -312,6 +309,13 @@ namespace trrep
          */
         void sst_received(const wsrep_gtid_t& gtid, int error);
 
+        /*!
+         * This method must be called after the server initialization
+         * has been completed. The call has a side effect of changing
+         * the Server Context state to s_initialized.
+         */
+        void initialized();
+
         /*!
          *
          */
diff --git a/include/trrep/transaction_context.hpp b/include/trrep/transaction_context.hpp
index 1311178..41acfd9 100644
--- a/include/trrep/transaction_context.hpp
+++ b/include/trrep/transaction_context.hpp
@@ -150,7 +150,7 @@ namespace trrep
         void remove_fragments();
         void clear_fragments();
         void cleanup();
-        void debug_log_state(const std::string&) const;
+        void debug_log_state(const char*) const;
 
         trrep::provider& provider_;
         trrep::client_context& client_context_;
diff --git a/scripts/benchmark-provider.sh b/scripts/benchmark-provider.sh
index 3b96e95..71dc9dd 100755
--- a/scripts/benchmark-provider.sh
+++ b/scripts/benchmark-provider.sh
@@ -17,11 +17,11 @@ function run_benchmark()
 }
 
 
-# for servers in 1 2 4 8 16
-for servers in 16
+for servers in 1 2 4 8 16
+# for servers in 16
 do
-#    for clients in 1 2 4 8 16 32
-    for clients in 4 8 16 32
+    for clients in 1 2 4 8 16 32
+#     for clients in 4 8 16 32
     do
 	run_benchmark $servers $clients
     done
diff --git a/src/dbms_simulator.cpp b/src/dbms_simulator.cpp
index edb28ed..3f30484 100644
--- a/src/dbms_simulator.cpp
+++ b/src/dbms_simulator.cpp
@@ -38,6 +38,7 @@ struct dbms_simulator_params
     size_t n_servers;
     size_t n_clients;
     size_t n_transactions;
+    size_t alg_freq;
     std::string wsrep_provider;
     std::string wsrep_provider_options;
     int debug_log_level;
@@ -46,6 +47,7 @@ struct dbms_simulator_params
         : n_servers(0)
         , n_clients(0)
         , n_transactions(0)
+        , alg_freq(0)
         , wsrep_provider()
         , wsrep_provider_options()
         , debug_log_level(0)
@@ -56,10 +58,10 @@ struct dbms_simulator_params
 class dbms_storage_engine
 {
 public:
-    dbms_storage_engine()
+    dbms_storage_engine(const dbms_simulator_params& params)
         : mutex_()
         , transactions_()
-        , alg_freq_(0)
+        , alg_freq_(params.alg_freq)
         , bf_aborts_()
     { }
 
@@ -212,7 +214,7 @@ public:
                                 name, id, address, name + "_data",
                                 trrep::server_context::rm_async)
         , simulator_(simulator)
-        , storage_engine_()
+        , storage_engine_(simulator_.params())
         , mutex_()
         , cond_()
         , last_client_id_(0)
@@ -372,8 +374,8 @@ private:
     bool killed() const override { return false; }
     void abort() const override { ::abort(); }
     void store_globals() override { }
-    void debug_sync(const std::string&) override { }
-    void debug_suicide(const std::string&) override { }
+    void debug_sync(const char*) override { }
+    void debug_suicide(const char*) override { }
     void on_error(enum trrep::client_error) override { }
 
     template <class Func>
@@ -714,6 +716,8 @@ int main(int argc, char** argv)
              "number of clients to start per server")
             ("transactions", po::value<size_t>(&params.n_transactions),
              "number of transactions run by a client")
+            ("alg-freq", po::value<size_t>(&params.alg_freq),
+             "ALG frequency")
             ("debug-log-level", po::value<int>(&params.debug_log_level),
              "debug logging level: 0 - none, 1 - verbose")
             ("fast-exit", po::value<int>(&params.fast_exit),
diff --git a/src/mock_client_context.hpp b/src/mock_client_context.hpp
index dc9c8b7..9472268 100644
--- a/src/mock_client_context.hpp
+++ b/src/mock_client_context.hpp
@@ -50,8 +50,8 @@ namespace trrep
         bool killed() const TRREP_OVERRIDE { return false; }
         void abort() const TRREP_OVERRIDE { }
         void store_globals() TRREP_OVERRIDE { }
-        void debug_sync(const std::string&) TRREP_OVERRIDE { }
-        void debug_suicide(const std::string&) TRREP_OVERRIDE
+        void debug_sync(const char*) TRREP_OVERRIDE { }
+        void debug_suicide(const char*) TRREP_OVERRIDE
         {
             ::abort();
         }
diff --git a/src/transaction_context.cpp b/src/transaction_context.cpp
index 4c02c9d..b6a0ded 100644
--- a/src/transaction_context.cpp
+++ b/src/transaction_context.cpp
@@ -131,6 +131,9 @@ int trrep::transaction_context::before_prepare()
     case trrep::client_context::m_local:
     case trrep::client_context::m_applier:
         break;
+    default:
+        assert(0);
+        break;
     }
 
     assert(state() == s_preparing);
@@ -174,6 +177,9 @@ int trrep::transaction_context::after_prepare()
         state(lock, s_committing);
         ret = 0;
         break;
+    default:
+        assert(0);
+        break;
     }
     debug_log_state("after_prepare_leave");
     return ret;
@@ -267,6 +273,9 @@ int trrep::transaction_context::before_commit()
             }
         }
         break;
+    default:
+        assert(0);
+        break;
     }
     debug_log_state("before_commit_leave");
     return ret;
@@ -310,6 +319,9 @@ int trrep::transaction_context::after_commit()
         break;
     case trrep::client_context::m_applier:
         break;
+    default:
+        assert(0);
+        break;
     }
     assert(ret == 0);
     state(lock, s_committed);
@@ -806,7 +818,7 @@ void trrep::transaction_context::cleanup()
 }
 
 void trrep::transaction_context::debug_log_state(
-    const std::string& context TRREP_UNUSED) const
+    const char* context) const
 {
     if (client_context_.debug_log_level() >= 1)
     {
diff --git a/wsrep b/wsrep
index 955da1c..e12a9dd 160000
--- a/wsrep
+++ b/wsrep
@@ -1 +1 @@
-Subproject commit 955da1c8c28bafd4bd8f625e53182f6e78459d4b
+Subproject commit e12a9dd89c18f7b426cd724cbdb28f213268b42c