Connected respurce model outputs for CPU limits to Dockernet API. Closes #47

[osm/vim-emu.git] / src / emuvim / dcemulator / node.py

diff --git a/src/emuvim/dcemulator/node.py b/src/emuvim/dcemulator/node.py
index d9971c8..7746e9e 100755 (executable)
--- a/src/emuvim/dcemulator/node.py
+++ b/src/emuvim/dcemulator/node.py
@@ -6,6 +6,9 @@ from mininet.node import Docker
 from mininet.link import Link
 import logging
 
+LOG = logging.getLogger("dcemulator")
+LOG.setLevel(logging.DEBUG)
+
 
 DCDPID_BASE = 1000  # start of switch dpid's used for data center switches
 
@@ -21,10 +24,9 @@ class EmulatorCompute(Docker):
 
     def __init__(
             self, name, dimage, **kwargs):
-        logging.debug("Create EmulatorCompute instance: %s" % name)
         self.datacenter = kwargs.get("datacenter")  # pointer to current DC
         self.flavor_name = kwargs.get("flavor_name")
-
+        LOG.debug("Starting compute instance %r in data center %r" % (name, str(self.datacenter)))
         # call original Docker.__init__
         Docker.__init__(self, name, dimage, **kwargs)
 
@@ -103,7 +105,7 @@ class Datacenter(object):
         """
         self.switch = self.net.addSwitch(
             "%s.s1" % self.name, dpid=hex(self._get_next_dc_dpid())[2:])
-        logging.debug("created data center switch: %s" % str(self.switch))
+        LOG.debug("created data center switch: %s" % str(self.switch))
 
     def start(self):
         pass
@@ -135,17 +137,37 @@ class Datacenter(object):
                 network.append({})
 
         # allocate in resource resource model and compute resource limits for new container
+        cpu_limit = mem_limit = disk_limit = -1
+        cpu_period = cpu_quota = None
         if self._resource_model is not None:
-            # TODO pass resource limits to new container (cf. Dockernet API) Issue #47
+            # call allocate in resource model to calculate resource limit for this container
             (cpu_limit, mem_limit, disk_limit) = alloc = self._resource_model.allocate(name, flavor_name)
-            logging.info("Allocation result: %r" % str(alloc))
+            LOG.debug("Allocation result: %r" % str(alloc))
+            # check if we have a cpu_limit given by the used resource model
+            if cpu_limit > 0:
+                # calculate cpu period and quota for CFS
+                # (see: https://www.kernel.org/doc/Documentation/scheduler/sched-bwc.txt)
+                # TODO consider multi core machines etc! non trivial!
+                # Attention minimum cpu_quota is 1ms (micro)
+                cpu_period = 100000  # lets consider a fixed period of 100000 microseconds for now
+                cpu_quota = cpu_period * cpu_limit  # calculate the fraction of cpu time for this container
+                LOG.debug(
+                    "CPU limit: cpu_quota = cpu_period * cpu_limit = %f * %f = %f" % (cpu_period, cpu_limit, cpu_quota))
+                # ATTENTION >= 1000 to avoid a invalid argument system error ... no idea why
+                if cpu_quota < 1000:
+                    cpu_quota = 1000
+                    LOG.warning("Increased CPU quota for %d to avoid system error." % name)
+            # TODO add memory and disc limitations
         # create the container
         d = self.net.addDocker(
             "%s" % (name),
             dimage=image,
             dcmd=command,
             datacenter=self,
-            flavor_name=flavor_name)
+            flavor_name=flavor_name,
+            cpu_period=int(cpu_period) if cpu_limit > 0 else None,  # set cpu limits if needed
+            cpu_quota=int(cpu_quota) if cpu_limit > 0 else None,
+        )
         # connect all given networks
         for nw in network:
             # TODO we cannot use TCLink here (see: https://github.com/mpeuster/dockernet/issues/3)
@@ -190,9 +212,14 @@ class Datacenter(object):
         }
 
     def assignResourceModel(self, rm):
+        """
+        Assign a resource model to this DC.
+        :param rm: a BaseResourceModel object
+        :return:
+        """
         if self._resource_model is not None:
             raise Exception("There is already an resource model assigned to this DC.")
         self._resource_model = rm
         self.net.rm_registrar.register(self, rm)
-        logging.info("Assigned RM: %r to DC: %r" % (rm, self))
+        LOG.info("Assigned RM: %r to DC: %r" % (rm, self))