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# Create an OVS bridge with OpenFlow enabled
ovs-vsctl add-br br0
 
# Configure OpenFlow controller
ovs-vsctl set-controller br0 tcp:192.168.1.100:6653
 
# Set OpenFlow version (1.3)
ovs-vsctl set bridge br0 protocols=OpenFlow13
 
# Add physical ports to bridge
ovs-vsctl add-port br0 eth0
ovs-vsctl add-port br0 eth1
 
# Add internal port (for host access)
ovs-vsctl add-port br0 internal0 -- set Interface internal0 type=internal
 
# Configure fail mode (secure = drop on controller failure)
ovs-vsctl set-fail-mode br0 secure
 
# View OpenFlow flows
ovs-ofctl -O OpenFlow13 dump-flows br0
 
# Manually add a flow (for testing)
ovs-ofctl -O OpenFlow13 add-flow br0 \
    "priority=100,ip,nw_dst=10.0.0.1,actions=output:2"
 
# View switch statistics
ovs-ofctl -O OpenFlow13 dump-ports br0
 
# Enable DPDK for high performance
ovs-vsctl set Open_vSwitch . other_config:dpdk-init=true
ovs-vsctl add-br br-dpdk -- set bridge br-dpdk datapath_type=netdev
ovs-vsctl add-port br-dpdk dpdk0 -- set Interface dpdk0 type=dpdk \
    options:dpdk-devargs=0000:03:00.0

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# Enable hardware offload in OVS
ovs-vsctl set Open_vSwitch . other_config:hw-offload=true
 
# Enable TC (traffic control) flower offload
ovs-vsctl set Open_vSwitch . other_config:tc-policy=skip_sw
 
# Verify offload is working
ovs-appctl dpctl/dump-flows --names type=offloaded
# Output shows flows handled by NIC hardware
 
# Check NIC offload statistics
ethtool -S enp3s0f0 | grep offload
 
# Example offloaded flow (from dump-flows):
# recirc_id(0),in_port(eth0),eth(src=...,dst=...),eth_type(0x0800),
# ipv4(src=10.0.0.1,dst=10.0.0.2), packets:1000000, bytes:64000000,
# used:0.001s, offloaded:yes, dp:tc, actions:output(eth1)

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"""
OpenFlow Switch Benchmarking Framework
Tests flow capacity, flow setup rate, and PACKET_IN handling.
"""
 
import time
from ryu.controller import ofp_event
from ryu.controller.handler import set_ev_cls, MAIN_DISPATCHER
 
class SwitchBenchmarker:
    """Benchmark OpenFlow switch capabilities."""
    
    def __init__(self):
        self.test_results = {}
    
    def test_flow_capacity(self, datapath, max_flows=100000):
        """
        Test maximum flow table capacity.
        Progressively install flows until errors.
        """
        parser = datapath.ofproto_parser
        ofproto = datapath.ofproto
        
        successful_flows = 0
        start_time = time.time()
        
        for i in range(max_flows):
            # Generate unique match per flow
            match = parser.OFPMatch(
                eth_type=0x0800,
                ipv4_dst=self._int_to_ip(0x0A000000 + i)  # 10.x.x.x
            )
            
            actions = [parser.OFPActionOutput(1)]
            inst = [parser.OFPInstructionActions(
                ofproto.OFPIT_APPLY_ACTIONS, actions)]
            
            mod = parser.OFPFlowMod(
                datapath=datapath,
                priority=100,
                match=match,
                instructions=inst
            )
            
            try:
                datapath.send_msg(mod)
                successful_flows += 1
                
                # Periodically check for errors via barrier
                if i % 1000 == 0:
                    barrier = parser.OFPBarrierRequest(datapath)
                    datapath.send_msg(barrier)
                    # Small delay to receive potential errors
                    time.sleep(0.01)
                    
            except Exception as e:
                print(f"Flow installation failed at {i}: {e}")
                break
        
        elapsed = time.time() - start_time
        
        self.test_results['flow_capacity'] = {
            'max_flows': successful_flows,
            'time_seconds': elapsed,
            'flows_per_second': successful_flows / elapsed
        }
        
        return self.test_results['flow_capacity']
    
    def test_flow_setup_rate(self, datapath, duration_sec=10):
        """
        Test sustained flow installation rate.
        Install flows as fast as possible for duration.
        """
        parser = datapath.ofproto_parser
        ofproto = datapath.ofproto
        
        # First, clear existing flows
        self._clear_all_flows(datapath)
        
        start_time = time.time()
        flows_installed = 0
        
        while time.time() - start_time < duration_sec:
            # Install batch of 100 flows
            for i in range(100):
                match = parser.OFPMatch(
                    eth_type=0x0800,
                    ipv4_dst=self._int_to_ip(0x0A000000 + flows_installed)
                )
                
                actions = [parser.OFPActionOutput(1)]
                inst = [parser.OFPInstructionActions(
                    ofproto.OFPIT_APPLY_ACTIONS, actions)]
                
                mod = parser.OFPFlowMod(
                    datapath=datapath,
                    priority=100,
                    match=match,
                    instructions=inst,
                    idle_timeout=5  # Auto-cleanup
                )
                datapath.send_msg(mod)
                flows_installed += 1
            
            # Barrier every batch
            barrier = parser.OFPBarrierRequest(datapath)
            datapath.send_msg(barrier)
        
        elapsed = time.time() - start_time
        
        self.test_results['flow_setup_rate'] = {
            'total_flows': flows_installed,
            'duration_sec': elapsed,
            'flows_per_second': flows_installed / elapsed
        }
        
        return self.test_results['flow_setup_rate']
    
    def test_packet_in_rate(self, datapath, duration_sec=10):
        """
        Test PACKET_IN handling rate.
        Count PACKET_IN messages received over duration.
        Requires external traffic generator sending unknown flows.
        """
        self._packet_in_count = 0
        self._test_start = time.time()
        self._test_duration = duration_sec
        
        # Table-miss should be configured to send to controller
        # External traffic generator sends unique flows
        
        # Handler increments count (see _packet_in_handler)
        time.sleep(duration_sec)
        
        self.test_results['packet_in_rate'] = {
            'total_packet_in': self._packet_in_count,
            'duration_sec': duration_sec,
            'packet_in_per_second': self._packet_in_count / duration_sec
        }
        
        return self.test_results['packet_in_rate']
    
    @set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
    def _packet_in_handler(self, ev):
        """Count PACKET_IN messages during test."""
        if hasattr(self, '_test_start'):
            elapsed = time.time() - self._test_start
            if elapsed < self._test_duration:
                self._packet_in_count += 1
    
    def _int_to_ip(self, ip_int):
        """Convert integer to IP address string."""
        return '.'.join([str((ip_int >> i) & 0xFF) for i in [24, 16, 8, 0]])
    
    def _clear_all_flows(self, datapath):
        """Delete all flows from switch."""
        parser = datapath.ofproto_parser
        ofproto = datapath.ofproto
        
        match = parser.OFPMatch()
        mod = parser.OFPFlowMod(
            datapath=datapath,
            command=ofproto.OFPFC_DELETE,
            out_port=ofproto.OFPP_ANY,
            out_group=ofproto.OFPG_ANY,
            match=match
        )
        datapath.send_msg(mod)
        
        barrier = parser.OFPBarrierRequest(datapath)
        datapath.send_msg(barrier)
        time.sleep(0.5)