[[cluster-stats]]
== Cluster Stats

The Cluster Stats API allows to retrieve statistics from a cluster wide perspective.
The API returns basic index metrics (shard numbers, store size, memory usage) and
information about the current nodes that form the cluster (number, roles, os, jvm
versions, memory usage, cpu and installed plugins).

[source,js]
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curl -XGET 'http://localhost:9200/_cluster/stats?human&pretty'
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Will return, for example:
["source","js",subs="attributes,callouts"]
--------------------------------------------------
{
   "cluster_name": "elasticsearch",
   "status": "green",
   "indices": {
      "count": 3,
      "shards": {
         "total": 35,
         "primaries": 15,
         "replication": 1.333333333333333,
         "index": {
            "shards": {
               "min": 10,
               "max": 15,
               "avg": 11.66666666666666
            },
            "primaries": {
               "min": 5,
               "max": 5,
               "avg": 5
            },
            "replication": {
               "min": 1,
               "max": 2,
               "avg": 1.3333333333333333
            }
         }
      },
      "docs": {
         "count": 2,
         "deleted": 0
      },
      "store": {
         "size": "5.6kb",
         "size_in_bytes": 5770,
         "throttle_time": "0s",
         "throttle_time_in_millis": 0
      },
      "fielddata": {
         "memory_size": "0b",
         "memory_size_in_bytes": 0,
         "evictions": 0
      },
      "filter_cache": {
         "memory_size": "0b",
         "memory_size_in_bytes": 0,
         "evictions": 0
      },
      "id_cache": {
         "memory_size": "0b",
         "memory_size_in_bytes": 0
      },
      "completion": {
         "size": "0b",
         "size_in_bytes": 0
      },
      "segments": {
         "count": 2
      }
   },
   "nodes": {
      "count": {
         "total": 2,
         "master_only": 0,
         "data_only": 0,
         "master_data": 2,
         "client": 0
      },
      "versions": [
         "{version}"
      ],
      "os": {
         "available_processors": 4,
         "mem": {
            "total": "8gb",
            "total_in_bytes": 8589934592
         },
         "cpu": [
            {
               "vendor": "Intel",
               "model": "MacBookAir5,2",
               "mhz": 2000,
               "total_cores": 4,
               "total_sockets": 4,
               "cores_per_socket": 16,
               "cache_size": "256b",
               "cache_size_in_bytes": 256,
               "count": 1
            }
         ]
      },
      "process": {
         "cpu": {
            "percent": 3
         },
         "open_file_descriptors": {
            "min": 200,
            "max": 346,
            "avg": 273
         }
      },
      "jvm": {
         "max_uptime": "24s",
         "max_uptime_in_millis": 24054,
         "versions": [
            {
               "version": "1.6.0_45",
               "vm_name": "Java HotSpot(TM) 64-Bit Server VM",
               "vm_version": "20.45-b01-451",
               "vm_vendor": "Apple Inc.",
               "count": 2
            }
         ],
         "mem": {
            "heap_used": "38.3mb",
            "heap_used_in_bytes": 40237120,
            "heap_max": "1.9gb",
            "heap_max_in_bytes": 2130051072
         },
         "threads": 89
      },
      "fs":
         {
            "total": "232.9gb",
            "total_in_bytes": 250140434432,
            "free": "31.3gb",
            "free_in_bytes": 33705881600,
            "available": "31.1gb",
            "available_in_bytes": 33443737600,
            "disk_reads": 21202753,
            "disk_writes": 27028840,
            "disk_io_op": 48231593,
            "disk_read_size": "528gb",
            "disk_read_size_in_bytes": 566980806656,
            "disk_write_size": "617.9gb",
            "disk_write_size_in_bytes": 663525366784,
            "disk_io_size": "1145.9gb",
            "disk_io_size_in_bytes": 1230506173440
       },
      "plugins": [
         // all plugins installed on nodes
         {
            "name": "inquisitor",
            "description": "",
            "url": "/_plugin/inquisitor/",
            "jvm": false,
            "site": true
         }
      ]
   }
}
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