Node memory > 95 % rest nodes are below 60%

[Rohit_Singh]

I have a 3 node cluster, all nodes are master data enabled. this cluster is running from past 4 days and receiving data. Today when i noticed node stats , one node was particulay showing memory usage > 95% while other nodes were around 50 to 60 %. Is this an memory leak.

Cluster details (elasticsearch is running in cluster)
JDK 1.8.0.91
ELasticsearch 2.3.1
Docker version 17.05
Verified there are no cirquit breakers, field data is limited under 12 k (limit is 830million), no queries are running.

Following is output of node stats

{
	"cluster_name": "elasticsearch_elk",
	"nodes": {
		"7jRkL2H4T5CCT5U2rdAqng": {
			"timestamp": 1509450797871,
			"name": "testing-perf-3",
			"transport_address": "192.x.x.x:4001",
			"host": "192.x.x.x",
			"ip": [
				"192.x.x.x:4001",
				"NONE"
			],
			"attributes": {
				"local": "false",
				"master": "true"
			},
			"os": {
				"timestamp": 1509450797681,
				"cpu_percent": 40,
				"load_average": 16.77,
				"mem": {
					"total_in_bytes": 67541999616,
					"free_in_bytes": 4320821248,
					"used_in_bytes": 63221178368,
					"free_percent": 6,
					"used_percent": 94
				},
				"swap": {
					"total_in_bytes": 0,
					"free_in_bytes": 0,
					"used_in_bytes": 0
				}
			}
		},
		"iDJUxUpsQHK4eK5wXtpvqg": {
			"timestamp": 1509450797869,
			"name": "testing-perf-2",
			"transport_address": "testing-perf-2/192.x.x.x.47:4001",
			"host": "192.x.x.x",
			"ip": [
				"testing-perf-2/192.x.x.x:4001",
				"NONE"
			],
			"attributes": {
				"local": "false",
				"master": "true"
			},
			"os": {
				"timestamp": 1509450797869,
				"cpu_percent": 6,
				"load_average": 2.82,
				"mem": {
					"total_in_bytes": 67541999616,
					"free_in_bytes": 38662205440,
					"used_in_bytes": 28879794176,
					"free_percent": 57,
					"used_percent": 43
				},
				"swap": {
					"total_in_bytes": 0,
					"free_in_bytes": 0,
					"used_in_bytes": 0
				}
			}
		},
		"j5PcKQehT66aXVQ8VQM04A": {
			"timestamp": 1509450797874,
			"name": "testing-perf-1",
			"transport_address": "192.0.x.x:4001",
			"host": "182.x.x.x.41",
			"ip": [
				"192.x.x.x:4001",
				"NONE"
			],
			"attributes": {
				"local": "false",
				"master": "true"
			},
			"os": {
				"timestamp": 1509450797874,
				"cpu_percent": 68,
				"load_average": 21.06,
				"mem": {
					"total_in_bytes": 67541999616,
					"free_in_bytes": 46190690304,
					"used_in_bytes": 21351309312,
					"free_percent": 68,
					"used_percent": 32
				},
				"swap": {
					"total_in_bytes": 0,
					"free_in_bytes": 0,
					"used_in_bytes": 0
				}
			}
		}
	}
}