nova-compute的虚拟机创建调度策略

版权声明：可以任意转载，转载时请务必以超链接形式标明文章原始出处!

文件 nova/scheduler/filter_scheduler.py

class FilterScheduler(driver.Scheduler)

->def schedule_run_instance

->self._schedule

->_schedule

->least_cost.weighted_sum

文件nova/schedul/least_cost.py

def weighted_sum

.........................

for host_state in host_states:

score = sum(weight * fn(host_state, weighing_properties)

for weight, fn in weighted_fns)

if min_score is None or score < min_score:

min_score, best_host = score, host_state

return WeightedHost(min_score, host_state=best_host)

每种调度策略给不同的权重，使用不同的调度策略根据物理主机的状态计算一个得分，得分与权重做乘运算，然后所有调度策略得分相加，计算出一个物理主机的和值，根据此值进行虚拟机实例的创建调度。