uint32_t max_streams; /**< max number of streams in context. */
uint32_t max_stream_rbufs; /**< max recv mbufs per stream. */
uint32_t max_stream_sbufs; /**< max send mbufs per stream. */
+ uint32_t send_bulk_size; /**< expected # of packets per send call. */
int (*lookup4)(void *opaque, const struct in_addr *addr,
struct tle_udp_dest *res);