一、Yarn
以获取Yarn界面队列信息为例：
1. 接口（HTTP Request）
http://ip:port/ws/v1/cluster/scheduler
ip和port：Yarn ResourceManager active节点的ip地址和端口号
2. 请求方式
GET
3. Response Header
代码语言：javascript复制HTTP/1.1 200 OK
Content-Type: application/json
Transfer-Encoding: chunked
Server: Jetty(6.1.26)4. Response Body
Yarn web ui显示的队列信息：
请求http://bigdatalearnshare01:8088/ws/v1/cluster/scheduler：
代码语言：javascript复制{
"scheduler":{
"schedulerInfo":{
"type":"capacityScheduler", -- 调度器类型
"capacity":100,
"usedCapacity":14.583333,
"maxCapacity":100,
"queueName":"root", -- root为根队列
"queues":{
"queue":[
{
"type":"capacitySchedulerLeafQueueInfo",
"capacity":20, -- 分配的容量（占整个队列的百分比）
"usedCapacity":20.83418, -- 使用队列容量（占当前队列的百分比）
"maxCapacity":20,
"absoluteCapacity":20,
"absoluteMaxCapacity":20,
"absoluteUsedCapacity":4.166667,
"numApplications":1,
"queueName":"default", -- 队列名字
"state":"RUNNING", -- 运行状态
"resourcesUsed":{"memory":2048,"vCores":2},
"hideReservationQueues":false,
"nodeLabels":["*"],
"allocatedContainers":2,
"reservedContainers":0,
"pendingContainers":0,
"capacities":{
"queueCapacitiesByPartition":[
{"partitionName":"","capacity":20,"usedCapacity":20.83418,"maxCapacity":20,
"absoluteCapacity":20,"absoluteUsedCapacity":4.166667,
"absoluteMaxCapacity":20,"maxAMLimitPercentage":50}
]
},
"resources":{
"resourceUsagesByPartition":[
{
"partitionName":"",
"used":{"memory":2048,"vCores":2},
"reserved":{"memory":0,"vCores":0},
"pending":{"memory":0,"vCores":0},
"amUsed":{"memory":1024,"vCores":1},
"amLimit":{"memory":5120,"vCores":1}
}
]
},
"numActiveApplications":1,
"numPendingApplications":0,
"numContainers":2,
"maxApplications":2000,
"maxApplicationsPerUser":2000,
"userLimit":100,
"users":{
"user":[
{
"username":"bigdatalearnshare",
"resourcesUsed":{
"memory":2048,
"vCores":2
},
"numPendingApplications":0,
"numActiveApplications":1,
"AMResourceUsed":{
"memory":1024,
"vCores":1
},
"userResourceLimit":{
"memory":10240,
"vCores":1
},
....
....
以下具体的接口功能和返回数据中的指标信息，参考官方文档：http://hadoop.apache.org/docs/r2.6.4/hadoop-yarn/hadoop-yarn-site/ResourceManagerRest.html。
二、Spark UI
以获取Spark UI界面executors指标信息为例：
以bigdatalearnshare01:8088的Yarn上的Spark应用实例为例，对应的Spark UI界面Executors主要信息如下：
Spark提供了很多接口去获取这些信息，比如：
同时，在Spark源码中，会有executorpage.js文件，里面也有相关接口的调用与指标信息的处理等，有兴趣的同学可以下载相关Spark版本的文件参考。
当然，Spark官网也有相关的介绍：http://spark.apache.org/docs/2.4.1/monitoring.html。
