1.通过/_cat/indices/ api查看所有index的段情况和当前正在进行merge的文档数。
GET /_cat/indices/?s=segmentsCount:desc&v&h=index,segmentsCount,segmentsMemory,memoryTotal,mergesCurrent,mergesCurrentDocs,storeSize,p,r
2.查看各个节点forceMerge的线程数
GET _cat/thread_pool/force_merge?v&s=name
3.查看forceMerge任务详情
GET _tasks?detailed=true&actions=*forcemerge
4.查看某个index的forceMerge情况
GET /_cat/segments/test-000032?v&s=prirep,shard