JVM reached above 70% in client node without any request serve

JVM of client node reached above 70% in an ideal state of the cluster. Is there any reason to increase JVM without any request? The number of shards and instance memory is optimal.

What version?
What is the output from the _cluster/stats?pretty&human API?

{ _nodes: { total: 13, successful: 13, failed: 0 }, cluster_name: "xxxxxxx", cluster_uuid: "lBlH3VSmS4m0oYBxdVUgmg", timestamp: 1611722987835, status: "green", indices: { count: 7, shards: { total: 146, primaries: 145, replication: 0.006896551724137931, index: { shards: { min: 1, max: 134, avg: 20.857142857142858 }, primaries: { min: 1, max: 134, avg: 20.714285714285715 }, replication: { min: 0, max: 1, avg: 0.14285714285714285 } } }, docs: { count: 10199973735, deleted: 70542562 }, store: { size: "5.5tb", size_in_bytes: 6103611348957 }, fielddata: { memory_size: "8.4gb", memory_size_in_bytes: 9097698200, evictions: 0 }, query_cache: { memory_size: "391.5kb", memory_size_in_bytes: 400976, total_count: 31958, hit_count: 1350, miss_count: 30608, cache_size: 269, cache_count: 388, evictions: 119 }, completion: { size: "0b", size_in_bytes: 0 }, segments: { count: 4975, memory: "1.3gb", memory_in_bytes: 1482895462, terms_memory: "420.1mb", terms_memory_in_bytes: 440568790, stored_fields_memory: "827.9mb", stored_fields_memory_in_bytes: 868136432, term_vectors_memory: "0b", term_vectors_memory_in_bytes: 0, norms_memory: "30.1mb", norms_memory_in_bytes: 31565056, points_memory: "0b", points_memory_in_bytes: 0, doc_values_memory: "136mb", doc_values_memory_in_bytes: 142625184, index_writer_memory: "0b", index_writer_memory_in_bytes: 0, version_map_memory: "0b", version_map_memory_in_bytes: 0, fixed_bit_set: "607.3mb", fixed_bit_set_memory_in_bytes: 636813224, max_unsafe_auto_id_timestamp: -1, file_sizes: { } } }, nodes: { count: { total: 13, coordinating_only: 0, data: 8, ingest: 13, master: 3, ml: 0, voting_only: 0 }, versions: [ "7.6.0" ], os: { available_processors: 328, allocated_processors: 328, names: [ { name: "Linux", count: 13 } ], pretty_names: [ { pretty_name: "CentOS Linux 7 (Core)", count: 13 } ], mem: { total: "717.4gb", total_in_bytes: 770336743424, free: "71.2gb", free_in_bytes: 76554579968, used: "646.1gb", used_in_bytes: 693782163456, free_percent: 10, used_percent: 90 } }, process: { cpu: { percent: 1 }, open_file_descriptors: { min: 620, max: 1508, avg: 1177 } }, jvm: { max_uptime: "5.8d", max_uptime_in_millis: 501311016, versions: [ { version: "1.8.0_232", vm_name: "OpenJDK 64-Bit Server VM", vm_version: "25.232-b09", vm_vendor: "AdoptOpenJDK", bundled_jdk: true, using_bundled_jdk: false, count: 13 } ], mem: { heap_used: "124gb", heap_used_in_bytes: 133169184272, heap_max: "310gb", heap_max_in_bytes: 332913967104 }, threads: 2359 }, fs: { total: "43.1tb", total_in_bytes: 47447384944640, free: "37.5tb", free_in_bytes: 41295796928512, available: "35.3tb", available_in_bytes: 38889541500928 }, plugins: [ { name: "discovery-ec2", version: "7.6.0", elasticsearch_version: "7.6.0", java_version: "1.8", description: "The EC2 discovery plugin allows to use AWS API for the unicast discovery mechanism.", classname: "org.elasticsearch.discovery.ec2.Ec2DiscoveryPlugin", extended_plugins: [ ], has_native_controller: false }, { name: "repository-s3", version: "7.6.0", elasticsearch_version: "7.6.0", java_version: "1.8", description: "The S3 repository plugin adds S3 repositories", classname: "org.elasticsearch.repositories.s3.S3RepositoryPlugin", extended_plugins: [ ], has_native_controller: false } ], network_types: { transport_types: { security4: 13 }, http_types: { security4: 13 } }, discovery_types: { zen: 13 }, packaging_types: [ { flavor: "default", type: "rpm", count: 13 } ], ingest: { number_of_pipelines: 2, processor_stats: { gsub: { count: 0, failed: 0, current: 0, time: "0s", time_in_millis: 0 }, script: { count: 0, failed: 0, current: 0, time: "0s", time_in_millis: 0 } } } } }

Any suggestions for this issue?