4 files changed, 53 insertions, 21 deletions
diff --git a/host/include/uhd/transport/udp_zero_copy.hpp b/host/include/uhd/transport/udp_zero_copy.hpp
index fd1cec46e..117f24b2f 100644
--- a/host/include/uhd/transport/udp_zero_copy.hpp
+++ b/host/include/uhd/transport/udp_zero_copy.hpp
@@ -52,6 +52,21 @@ public:
      * \param port a string representing the destination port
      */
     static sptr make(const std::string &addr, const std::string &port);
+
+    /*!
+     * The the rx buffer size on the socket.
+     * \param num_bytes the new size for the socket buffer
+     * \return the actual number of bytes allowed by the OS
+     */
+    virtual size_t set_recv_buff_size(size_t num_bytes) = 0;
+
+    /*!
+     * The the tx buffer size on the socket.
+     * \param num_bytes the new size for the socket buffer
+     * \return the actual number of bytes allowed by the OS
+     */
+    virtual size_t set_send_buff_size(size_t num_bytes) = 0;
+
 };
 
 }} //namespace
diff --git a/host/include/uhd/usrp/usrp2.hpp b/host/include/uhd/usrp/usrp2.hpp
index 613b40ae3..7387e5dd4 100644
--- a/host/include/uhd/usrp/usrp2.hpp
+++ b/host/include/uhd/usrp/usrp2.hpp
@@ -35,6 +35,10 @@ public:
      * hint["addr"] = address, where address is a resolvable address
      * or ip address, which may or may not be a broadcast address.
      *
+     * Other optional device address keys:
+     *   recv_buff_size: resizes the recv buffer on the data socket
+     *   send_buff_size: resizes the send buffer on the data socket
+     *
      * \param hint a device addr with the usrp2 address filled in
      * \return a vector of device addresses for all usrp2s found
      */
diff --git a/host/lib/transport/udp_zero_copy_asio.cpp b/host/lib/transport/udp_zero_copy_asio.cpp
index 7e643abad..315ae49d2 100644
--- a/host/lib/transport/udp_zero_copy_asio.cpp
+++ b/host/lib/transport/udp_zero_copy_asio.cpp
@@ -19,8 +19,6 @@
 #include <boost/cstdint.hpp>
 #include <boost/asio.hpp>
 #include <boost/thread.hpp>
-#include <boost/format.hpp>
-#include <iostream>
 
 using namespace uhd::transport;
 
@@ -104,12 +102,13 @@ public:
     managed_recv_buffer::sptr get_recv_buff(void);
     managed_send_buffer::sptr get_send_buff(void);
 
+    //resize
+    size_t set_recv_buff_size(size_t num_bytes);
+    size_t set_send_buff_size(size_t num_bytes);
+
 private:
     boost::asio::ip::udp::socket   *_socket;
     boost::asio::io_service        _io_service;
-
-    size_t get_recv_buff_size(void);
-    void set_recv_buff_size(size_t);
 };
 
 udp_zero_copy_impl::udp_zero_copy_impl(const std::string &addr, const std::string &port){
@@ -124,18 +123,6 @@ udp_zero_copy_impl::udp_zero_copy_impl(const std::string &addr, const std::strin
     _socket = new boost::asio::ip::udp::socket(_io_service);
     _socket->open(boost::asio::ip::udp::v4());
     _socket->connect(receiver_endpoint);
-
-    // set the rx socket buffer size:
-    // pick a huge size, and deal with whatever we get
-    set_recv_buff_size(size_t(54321e3)); //some big number!
-    size_t current_buff_size = get_recv_buff_size();
-    std::cout << boost::format(
-        "Current rx socket buffer size: %d\n"
-    ) % current_buff_size;
-    if (current_buff_size < size_t(.1e6)) std::cout << boost::format(
-        "Adjust max rx socket buffer size (linux only):\n"
-        "  sysctl -w net.core.rmem_max=VALUE\n"
-    );
 }
 
 udp_zero_copy_impl::~udp_zero_copy_impl(void){
@@ -170,15 +157,20 @@ managed_send_buffer::sptr udp_zero_copy_impl::get_send_buff(void){
     );
 }
 
-size_t udp_zero_copy_impl::get_recv_buff_size(void){
-    boost::asio::socket_base::receive_buffer_size option;
+//sysctl -w net.core.rmem_max=VALUE
+size_t udp_zero_copy_impl::set_recv_buff_size(size_t num_bytes){
+    boost::asio::socket_base::receive_buffer_size option(num_bytes);
+    _socket->set_option(option);
     _socket->get_option(option);
     return option.value();
 }
 
-void udp_zero_copy_impl::set_recv_buff_size(size_t new_size){
-    boost::asio::socket_base::receive_buffer_size option(new_size);
+//sysctl -w net.core.wmem_max=VALUE
+size_t udp_zero_copy_impl::set_send_buff_size(size_t num_bytes){
+    boost::asio::socket_base::send_buffer_size option(num_bytes);
     _socket->set_option(option);
+    _socket->get_option(option);
+    return option.value();
 }
 
 /***********************************************************************
diff --git a/host/lib/usrp/usrp2/usrp2_impl.cpp b/host/lib/usrp/usrp2/usrp2_impl.cpp
index 4079357f9..ffcdbb43d 100644
--- a/host/lib/usrp/usrp2/usrp2_impl.cpp
+++ b/host/lib/usrp/usrp2/usrp2_impl.cpp
@@ -24,6 +24,7 @@
 #include <boost/assign/list_of.hpp>
 #include <boost/format.hpp>
 #include <boost/foreach.hpp>
+#include <boost/lexical_cast.hpp>
 #include <boost/bind.hpp>
 #include <boost/asio.hpp> //htonl and ntohl
 #include <iostream>
@@ -117,6 +118,26 @@ device::sptr usrp2::make(const device_addr_t &device_addr){
         device_addr["addr"], num2str(USRP2_UDP_DATA_PORT)
     );
 
+    //resize the recv data transport buffers
+    if (device_addr.has_key("recv_buff_size")){
+        size_t num_byes = size_t(boost::lexical_cast<double>(device_addr["recv_buff_size"]));
+        size_t actual_bytes = data_transport->set_recv_buff_size(num_byes);
+        std::cout << boost::format(
+            "Target recv buffer size: %d"
+            "Actual recv byffer size: %d"
+        ) % num_byes % actual_bytes << std::endl;
+    }
+
+    //resize the send data transport buffers
+    if (device_addr.has_key("send_buff_size")){
+        size_t num_byes = size_t(boost::lexical_cast<double>(device_addr["send_buff_size"]));
+        size_t actual_bytes = data_transport->set_send_buff_size(num_byes);
+        std::cout << boost::format(
+            "Target send buffer size: %d"
+            "Actual send byffer size: %d"
+        ) % num_byes % actual_bytes << std::endl;
+    }
+
     //create the usrp2 implementation guts
     return device::sptr(
         new usrp2_impl(ctrl_transport, data_transport)