- # 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:
- # 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)
- 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