TD_XCHG_CONTEXT_NO_START_IO
TD_XCHG_CONTEXT_NO_START_IO(tiRoot) = 0;
TD_XCHG_CONTEXT_NO_START_IO(tiRoot) = TD_XCHG_CONTEXT_NO_START_IO(tiRoot)+1;
TD_XCHG_CONTEXT_NO_START_IO(tiRoot) = TD_XCHG_CONTEXT_NO_START_IO(tiRoot)+1;