Implement binding strategy in creating and binding lport

- see the guide: ansible/doc/binding-strategy.rst

Signed-off-by: Hui Kang <kangh@us.ibm.com>

ansible/doc/binding-strategy.rst

@@ -0,0 +1,51 @@
+======================
+Binding Strategy Guide
+======================
+
+Overview
+========
+
+In OVN, a logical port can be bind to a local OVS port on any
+chassis/hypervisor, depending on the VM scheduler (e.g., ``nova-scheduler``).
+The binding strategy potentially impacts the network performance. That is
+binding all logical ports from a logical network on a single hypervisor performs
+differently than distributing the ports on multiple hypervisors.
+
+The container-based ovn-scale-test deployment allows to configure the binding
+strategy in creating and binding port rally task.
+
+
+Binding Configuration
+=====================
+
+Use ``networks_per_sandbox`` to control how logical networks and the logical
+ports are bind to chassis.
+
+For example, given ``ovn_number_chassis: 10`` (4 emulated chassis) and
+``ovn_number_chassis: 10`` (10 logical networks), the binding varies depending
+on the value of ``networks_per_sandbox``.
+
+- ``networks_per_sandbox: "10"``: this is the default case. All networks will
+be evenly distributed to all chassis.
+
+- ``networks_per_sandbox: "2"``: each chassis has ports belong to two logical
+networks. In this case, the 10 logical networks are divided into 5 groups, say
+[n0, n1], [n2, n3], [n4, n5], [n6, n7], [n8, n9]. Then ports in [n0, n1] are
+bind to chassis 0 and 1, [n2, n3] to chassis 2 and 3, and so forth. As a
+result, each chassis has two logical network as configured.
+
+- ``networks_per_sandbox: "1"``: each chassis has ports belong to only one
+logical network. In this case, the 10 logical network will have a one-to-one
+mapping to the 10 chassis. Note that this is the extreme case as opposite to
+``networks_per_sandbox: "10"``.
+
+
+Constraint
+~~~~~~~~~
+
+TBD
+
+Implementation Detail
+=====================
+
+TBD

ansible/etc/variables.yml

@@ -37,6 +37,9 @@ network_start_cidr: "172.16.201.0/24"
 network_number: "5"
 ports_per_network: "5"
 
+# from 0 to network_number, 0 means even distribution (default)
+networks_per_sandbox: "0"
+
 acls_per_port: "1"
 
 ########################

ansible/group_vars/all.yml

@@ -44,6 +44,9 @@ ports_per_network: "1"
 ports_created_batch_size: "1"
 networks_created_batch_size: "1"
 
+# from 0 to network_number, 0 means even distribution (default)
+networks_per_sandbox: "0"
+
 acls_per_port: "1"
 
 ########################

ansible/roles/rally/templates/create_and_bind_ports.json.j2

@@ -12,6 +12,7 @@
                     "start_cidr": "{{ network_start_cidr }}",
                     "physical_network": "providernet"
                 },
+                "networks_per_sandbox": {{ networks_per_sandbox }},
                 "port_create_args" : {
                     "batch": {{ ports_created_batch_size }}
                 },

ci/ansible/all.yml

@@ -41,6 +41,9 @@ ports_created_batch_size: "1"
 networks_created_batch_size: "1"
 acls_per_port: "5"
 
+# from 0 to network_number, 0 means even distribution (default)
+networks_per_sandbox: "0"
+
 ################
 # OVS Repository
 ################

rally_ovs/plugins/ovs/scenarios/ovn_network.py

@@ -15,12 +15,105 @@
 from rally.common import logging
 from rally_ovs.plugins.ovs.scenarios import ovn
 
+from rally import exceptions
 from rally.task import scenario
 from rally.task import validation
 
 LOG = logging.getLogger(__name__)
 
+class LogicalNetwork():
+    def __init__(self):
+        self.sandboxes = []
+        self.ports_per_network = 0
 
+    def set_lswitch(self, lswitch):
+        self.lswitch = lswitch
+
+    def add_sandbox(self, sandbox):
+        self.sandboxes.append(sandbox)
+
+    def get_lswitch(self):
+        return self.lswitch
+
+    def get_sandboxes(self):
+        return self.sandboxes
+
+    def get_ports_per_network(self):
+        return self.ports_per_network
+
+
+def initialize_logical_networks(lswitches):
+    LOG.info("Initialize logical lswitches with %s" % lswitches)
+    logical_networks = []
+
+    for lswitch in lswitches:
+        logical_network = LogicalNetwork()
+        logical_network.set_lswitch(lswitch)
+        LOG.info("Logical network: %s" % logical_network.get_lswitch())
+        logical_networks.append(logical_network)
+
+    return logical_networks
+
+
+def allocate_networks_on_sandboxes(logical_networks, sandboxes, networks_per_sandbox=0):
+    if networks_per_sandbox == 0:
+        for logical_network in logical_networks:
+            for sandbox in sandboxes:
+                logical_network.add_sandbox(sandbox)
+    else:
+        # Sanity check
+        num_networks = len(logical_networks)
+
+        if (num_networks % networks_per_sandbox) != 0 :
+            message = ("Number of network %s is not divisible by network per sandbox %s")
+            raise exceptions.InvalidConfigException(
+                message  % (str(num_networks), str(networks_per_sandbox)))
+
+        LOG.info("Number of networks: %s" % str(num_networks))
+        num_network_groups = num_networks / networks_per_sandbox
+        LOG.info("Number of network group: %s" % str(num_network_groups))
+
+        if len(sandboxes) < num_network_groups :
+            message = ("Number of sandbox %d is less than number of network groups %d")
+            raise exceptions.InvalidConfigException(
+                message  % (len(sandboxes), num_network_groups))
+        elif (len(sandboxes) % num_network_groups) != 0 :
+            message = ("Number of sandbox %d is not divisible by network groups %d")
+            raise exceptions.InvalidConfigException(
+                message  % (len(sandboxes), num_network_groups))
+
+
+        group_spread_sandboxes = len(sandboxes) / num_network_groups
+        LOG.info("Number of group spread sandboxes: %s" % str(group_spread_sandboxes))
+
+        network_groups = []
+        networks_per_group = num_networks / num_network_groups
+        base = 0
+        for i in range(0, num_network_groups):
+            LOG.info("Group %d" % i)
+            network_group = []
+
+            for j in range(base, base + networks_per_group):
+                network_group.append(logical_networks[j])
+                LOG.info("\t%d, add logical network: %s" % (j, logical_networks[j].get_lswitch()))
+
+            LOG.info("network group idx0: %s" % network_group[0].get_lswitch())
+
+            network_groups.append(network_group)
+            base += networks_per_group
+
+        LOG.info("Allocating sandboxes...")
+        sandbox_idx = 0
+        base = 0
+        for group in network_groups:
+            for network in group:
+                LOG.info("network switch name: %s" % network.get_lswitch())
+                for sandbox_idx in range(base, base + group_spread_sandboxes):
+                    network.add_sandbox(sandboxes[sandbox_idx])
+                    LOG.info("\tAdd sandbox %s" % sandboxes[sandbox_idx])
+            base += group_spread_sandboxes
+
+    return logical_networks
 
 class OvnNetwork(ovn.OvnScenario):
     """scenarios for OVN network."""
@@ -35,16 +128,23 @@ def create_networks(self, network_create_args):
     @scenario.configure(context={})
     def create_and_bind_ports(self,
                               network_create_args=None,
+                              networks_per_sandbox=None,
                               port_create_args=None,
                               ports_per_network=None,
                               port_bind_args=None):
 
         sandboxes = self.context["sandboxes"]
 
         lswitches = self._create_networks(network_create_args)
-        for lswitch in lswitches:
-            lports = self._create_lports(lswitch, port_create_args, ports_per_network)
-            self._bind_ports(lports, sandboxes, port_bind_args)
+        logical_networks = []
+        logical_networks = initialize_logical_networks(lswitches)
+        if networks_per_sandbox == None:
+            networks_per_sandbox = 0
+        logical_networks = allocate_networks_on_sandboxes(logical_networks, sandboxes, networks_per_sandbox)
+
+        for logical_network in logical_networks:
+            lports = self._create_lports(logical_network.get_lswitch(), port_create_args, ports_per_network)
+            self._bind_ports(lports, logical_network.get_sandboxes(), port_bind_args)
 
 
     def bind_ports(self):