设置multiple Executor mode
即在azkaban-web-server中的azkaban.properties添加：
Multiple Executor Mode
azkaban.use.multiple.executors=true
azkaban.executorselector.filters=StaticRemainingFlowSize,MinimumFreeMemory,CpuStatus
azkaban.executorselector.comparator.NumberOfAssignedFlowComparator=1
azkaban.executorselector.comparator.Memory=1
azkaban.executorselector.comparator.LastDispatched=1
azkaban.executorselector.comparator.CpuUsage=1
比较因子为NumberOfAssignedFlowComparator、Memory、LastDispatched、CpuUsage 默认权重都是1
同时在数据库中插入Executor：
insert into executors(host,port) values("ExecutorIP",12321);
重启 AzkabanWebServer 进程
