diff --git a/src/backup.c b/src/backup.c
index 140188fb..1bf4e02f 100644
--- a/src/backup.c
+++ b/src/backup.c
@@ -2708,7 +2708,10 @@ pg_ptrack_get_block(backup_files_args *arguments,
 	sprintf(params[3], "%u", blknum);
 
 	if (arguments->thread_backup_conn == NULL)
+	{
 		arguments->thread_backup_conn = pgut_connect(pgut_dbname);
+	}
+	arguments->thread_cancel_conn = PQgetCancel(arguments->thread_backup_conn);
 
 	//elog(LOG, "db %i pg_ptrack_get_block(%i, %i, %u)",dbOid, tblsOid, relOid, blknum);
 	res = pgut_execute_parallel(arguments->thread_backup_conn,
diff --git a/src/pg_probackup.h b/src/pg_probackup.h
index c48c2357..743e670f 100644
--- a/src/pg_probackup.h
+++ b/src/pg_probackup.h
@@ -250,7 +250,7 @@ typedef struct
 	parray *prev_backup_filelist;
 	XLogRecPtr prev_backup_start_lsn;
 	PGconn *thread_backup_conn;
-	PGconn *thread_cancel_conn;
+	PGcancel *thread_cancel_conn;
 } backup_files_args;
 
 /*
diff --git a/src/utils/pgut.c b/src/utils/pgut.c
index b1abbcab..2627c24d 100644
--- a/src/utils/pgut.c
+++ b/src/utils/pgut.c
@@ -54,8 +54,8 @@ static bool parse_pair(const char buffer[], char key[], char value[]);
 
 /* Connection routines */
 static void init_cancel_handler(void);
-static void on_before_exec(PGconn *conn);
-static void on_after_exec(void);
+static void on_before_exec(PGconn *conn, PGcancel *thread_cancel_conn);
+static void on_after_exec(PGcancel *thread_cancel_conn);
 static void on_interrupt(void);
 static void on_cleanup(void);
 static void exit_or_abort(int exitcode);
@@ -1512,7 +1512,7 @@ pgut_set_port(const char *new_port)
 
 PGresult *
 pgut_execute_parallel(PGconn* conn, 
-					  PGconn* cancel_conn, const char *query, 
+					  PGcancel* thread_cancel_conn, const char *query, 
 					  int nParams, const char **params,
 					  bool text_result)
 {
@@ -1540,7 +1540,7 @@ pgut_execute_parallel(PGconn* conn,
 		return NULL;
 	}
 
-	//on_before_exec(conn);
+	on_before_exec(conn, thread_cancel_conn);
 	if (nParams == 0)
 		res = PQexec(conn, query);
 	else
@@ -1550,7 +1550,7 @@ pgut_execute_parallel(PGconn* conn,
 							* or one to obtain results in binary format.
 							*/
 						   (text_result) ? 0 : 1);
-	//on_after_exec();
+	on_after_exec(thread_cancel_conn);
 
 	switch (PQresultStatus(res))
 	{
@@ -1594,7 +1594,7 @@ pgut_execute(PGconn* conn, const char *query, int nParams, const char **params,
 		return NULL;
 	}
 
-	on_before_exec(conn);
+	on_before_exec(conn, NULL);
 	if (nParams == 0)
 		res = PQexec(conn, query);
 	else
@@ -1604,7 +1604,7 @@ pgut_execute(PGconn* conn, const char *query, int nParams, const char **params,
 							* or one to obtain results in binary format.
 							*/
 						   (text_result) ? 0 : 1);
-	on_after_exec();
+	on_after_exec(NULL);
 
 	switch (PQresultStatus(res))
 	{
@@ -1745,7 +1745,7 @@ static CRITICAL_SECTION cancelConnLock;
  * Set cancel_conn to point to the current database connection.
  */
 static void
-on_before_exec(PGconn *conn)
+on_before_exec(PGconn *conn, PGcancel *thread_cancel_conn)
 {
 	PGcancel   *old;
 
@@ -1756,16 +1756,32 @@ on_before_exec(PGconn *conn)
 	EnterCriticalSection(&cancelConnLock);
 #endif
 
-	/* Free the old one if we have one */
-	old = cancel_conn;
+	if (thread_cancel_conn)
+	{
+		elog(WARNING, "Handle tread_cancel_conn. on_before_exec");
+		old = thread_cancel_conn;
 
-	/* be sure handle_sigint doesn't use pointer while freeing */
-	cancel_conn = NULL;
+		/* be sure handle_sigint doesn't use pointer while freeing */
+		thread_cancel_conn = NULL;
 
-	if (old != NULL)
-		PQfreeCancel(old);
+		if (old != NULL)
+			PQfreeCancel(old);
 
-	cancel_conn = PQgetCancel(conn);
+		thread_cancel_conn = PQgetCancel(conn);
+	}
+	else
+	{
+		/* Free the old one if we have one */
+		old = cancel_conn;
+
+		/* be sure handle_sigint doesn't use pointer while freeing */
+		cancel_conn = NULL;
+
+		if (old != NULL)
+			PQfreeCancel(old);
+
+		cancel_conn = PQgetCancel(conn);
+	}
 
 #ifdef WIN32
 	LeaveCriticalSection(&cancelConnLock);
@@ -1778,7 +1794,7 @@ on_before_exec(PGconn *conn)
  * Free the current cancel connection, if any, and set to NULL.
  */
 static void
-on_after_exec(void)
+on_after_exec(PGcancel *thread_cancel_conn)
 {
 	PGcancel   *old;
 
@@ -1789,14 +1805,27 @@ on_after_exec(void)
 	EnterCriticalSection(&cancelConnLock);
 #endif
 
-	old = cancel_conn;
+	if (thread_cancel_conn)
+	{
+		elog(WARNING, "Handle tread_cancel_conn. on_after_exec");
+		old = thread_cancel_conn;
 
-	/* be sure handle_sigint doesn't use pointer while freeing */
-	cancel_conn = NULL;
+		/* be sure handle_sigint doesn't use pointer while freeing */
+		thread_cancel_conn = NULL;
 
-	if (old != NULL)
-		PQfreeCancel(old);
+		if (old != NULL)
+			PQfreeCancel(old);
+	}
+	else
+	{
+		old = cancel_conn;
 
+		/* be sure handle_sigint doesn't use pointer while freeing */
+		cancel_conn = NULL;
+
+		if (old != NULL)
+			PQfreeCancel(old);
+	}
 #ifdef WIN32
 	LeaveCriticalSection(&cancelConnLock);
 #endif
diff --git a/src/utils/pgut.h b/src/utils/pgut.h
index 1a35a48c..def0f9d2 100644
--- a/src/utils/pgut.h
+++ b/src/utils/pgut.h
@@ -127,7 +127,7 @@ extern PGconn *pgut_connect_replication_extended(const char *pghost, const char
 extern void pgut_disconnect(PGconn *conn);
 extern PGresult *pgut_execute(PGconn* conn, const char *query, int nParams,
 							  const char **params, bool text_result);
-extern PGresult *pgut_execute_parallel(PGconn* conn, PGconn* cancel_conn, 
+extern PGresult *pgut_execute_parallel(PGconn* conn, PGcancel* thread_cancel_conn, 
 							  const char *query, int nParams,
 							  const char **params, bool text_result);
 extern bool pgut_send(PGconn* conn, const char *query, int nParams, const char **params, int elevel);