+ def allocate(self, d):
+ """
+ Allocate resources for the given container.
+ Defined by d.flavor_name
+ :param d: container
+ :return:
+ """
+ self._allocated_compute_instances[d.name] = d
+ if not self.deactivate_cpu_limit:
+ self._allocate_cpu(d)
+ if not self.deactivate_mem_limit:
+ self._allocate_mem(d)
+ self._apply_limits()
+
+ def _allocate_cpu(self, d):
+ """
+ Actually allocate (bookkeeping)
+ :param d: container
+ :return:
+ """
+ fl_cu = self._get_flavor(d).get("compute")
+ # check for over provisioning
+ if self.dc_alloc_cu + fl_cu > self.dc_max_cu:
+ raise Exception("Not enough compute resources left.")
+ self.dc_alloc_cu += fl_cu
+
+ def _allocate_mem(self, d):
+ """
+ Actually allocate (bookkeeping)
+ :param d: container
+ :return:
+ """
+ fl_mu = self._get_flavor(d).get("memory")
+ # check for over provisioning
+ if self.dc_alloc_mu + fl_mu > self.dc_max_mu:
+ raise Exception("Not enough memory resources left.")
+ self.dc_alloc_mu += fl_mu
+
+ def free(self, d):
+ """
+ Free resources allocated to the given container.
+ :param d: container
+ :return:
+ """
+ del self._allocated_compute_instances[d.name]
+ if not self.deactivate_cpu_limit:
+ self._free_cpu(d)
+ if not self.deactivate_mem_limit:
+ self._free_mem(d)
+ self._apply_limits()
+
+ def _free_cpu(self, d):
+ """
+ Free resources.
+ :param d: container
+ :return:
+ """
+ self.dc_alloc_cu -= self._get_flavor(d).get("compute")
+
+ def _free_mem(self, d):
+ """
+ Free resources.
+ :param d: container
+ :return:
+ """
+ self.dc_alloc_mu -= self._get_flavor(d).get("memory")
+
+ def _apply_limits(self):
+ """
+ Recalculate real resource limits for all allocated containers and apply them
+ to their cgroups.
+ We have to recalculate for all to allow e.g. overprovisioning models.
+ :return:
+ """
+ for d in self._allocated_compute_instances.itervalues():
+ if not self.deactivate_cpu_limit:
+ self._apply_cpu_limits(d)
+ if not self.deactivate_mem_limit:
+ self._apply_mem_limits(d)
+
+ def _apply_cpu_limits(self, d):
+ """
+ Calculate real CPU limit (CFS bandwidth) and apply.
+ :param d: container
+ :return:
+ """
+ number_cu = self._get_flavor(d).get("compute")
+ # calculate cpu time fraction of a single compute unit
+ self.single_cu = self._compute_single_cu()
+ # calculate cpu time fraction for container with given flavor
+ cpu_time_percentage = self.single_cu * number_cu
+ # calculate input values for CFS scheduler bandwidth limitation
+ cpu_period, cpu_quota = self._calculate_cpu_cfs_values(cpu_time_percentage)
+ # apply limits to container if changed
+ if d.cpu_period != cpu_period or d.cpu_quota != cpu_quota:
+ LOG.debug("Setting CPU limit for %r: cpu_quota = cpu_period * limit = %f * %f = %f" % (
+ d.name, cpu_period, cpu_time_percentage, cpu_quota))
+ d.updateCpuLimit(cpu_period=int(cpu_period), cpu_quota=int(cpu_quota))
+
+ def _compute_single_cu(self):
+ """
+ Calculate percentage of CPU time of a singe CU unit.
+ :return:
+ """
+ # get cpu time fraction for entire emulation
+ e_cpu = self.registrar.e_cpu
+ # calculate
+ return float(e_cpu) / sum([rm.dc_max_cu for rm in list(self.registrar.resource_models)])
+
+ def _calculate_cpu_cfs_values(self, cpu_time_percentage):
+ """
+ Calculate cpu period and quota for CFS
+ :param cpu_time_percentage: percentage of overall CPU to be used
+ :return: cpu_period, cpu_quota
+ """
+ # (see: https://www.kernel.org/doc/Documentation/scheduler/sched-bwc.txt)
+ # Attention minimum cpu_quota is 1ms (micro)
+ cpu_period = CPU_PERIOD # lets consider a fixed period of 1000000 microseconds for now
+ cpu_quota = cpu_period * cpu_time_percentage # calculate the fraction of cpu time for this container
+ # ATTENTION >= 1000 to avoid a invalid argument system error ... no idea why
+ if cpu_quota < 1000:
+ cpu_quota = 1000
+ LOG.warning("Increased CPU quota to avoid system error.")
+ return cpu_period, cpu_quota
+
+ def _apply_mem_limits(self, d):
+ """
+ Calculate real mem limit and apply.
+ :param d: container
+ :return:
+ """
+ number_mu = self._get_flavor(d).get("memory")
+ # get memory amount for entire emulation
+ e_mem = self.registrar.e_mem
+ # calculate amount of memory for a single mu
+ self.single_mu = float(e_mem) / sum([rm.dc_max_mu for rm in list(self.registrar.resource_models)])
+ # calculate mem for given flavor
+ mem_limit = self.single_mu * number_mu
+ mem_limit = self._calculate_mem_limit_value(mem_limit)
+ # apply to container if changed
+ if d.mem_limit != mem_limit:
+ LOG.debug("Setting MEM limit for %r: mem_limit = %f MB" % (d.name, mem_limit/1024/1024))
+ d.updateMemoryLimit(mem_limit=mem_limit)
+
+ def _calculate_mem_limit_value(self, mem_limit):
+ """
+ Calculate actual mem limit as input for cgroup API
+ :param mem_limit: abstract mem limit
+ :return: concrete mem limit
+ """
+ # ATTENTION minimum mem_limit per container is 4MB
+ if mem_limit < 4:
+ mem_limit = 4
+ LOG.warning("Increased MEM limit because it was less than 4.0 MB.")
+ # to byte!
+ return int(mem_limit*1024*1024)
+
+ def get_state_dict(self):
+ """
+ Return the state of the resource model as simple dict.
+ Helper method for logging functionality.
+ :return:
+ """
+ # collect info about all allocated instances
+ allocation_state = dict()
+ for k, d in self._allocated_compute_instances.iteritems():
+ s = dict()
+ s["cpu_period"] = d.cpu_period
+ s["cpu_quota"] = d.cpu_quota
+ s["cpu_shares"] = d.cpu_shares
+ s["mem_limit"] = d.mem_limit
+ s["memswap_limit"] = d.memswap_limit
+ allocation_state[k] = s
+ # final result
+ r = dict()
+ r["e_cpu"] = self.registrar.e_cpu
+ r["e_mem"] = self.registrar.e_mem
+ r["dc_max_cu"] = self.dc_max_cu
+ r["dc_max_mu"] = self.dc_max_mu
+ r["dc_alloc_cu"] = self.dc_alloc_cu
+ r["dc_alloc_mu"] = self.dc_alloc_mu
+ r["single_cu_percentage"] = self.single_cu
+ r["single_mu_percentage"] = self.single_mu
+ r["allocation_state"] = allocation_state
+ return r
+
+ def _get_flavor(self, d):
+ """
+ Get flavor assigned to given container.
+ Identified by d.flavor_name.
+ :param d: container
+ :return:
+ """
+ if d.flavor_name not in self._flavors:
+ raise Exception("Flavor %r does not exist" % d.flavor_name)
+ return self._flavors.get(d.flavor_name)
+
+ def _write_log(self, d, path, action):
+ """
+ Helper to log RM info for experiments.
+ :param d: container
+ :param path: log path
+ :param action: allocate or free
+ :return:
+ """
+ if path is None:
+ return
+ # we have a path: write out RM info
+ l = dict()
+ l["t"] = time.time()
+ l["container_state"] = d.getStatus()
+ l["action"] = action
+ l["rm_state"] = self.get_state_dict()
+ # append to logfile
+ with open(path, "a") as f:
+ f.write("%s\n" % json.dumps(l))
projects / osm / vim-emu.git / blobdiff