Cache stats API

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Retrieves statistics about the shared cache for partially mounted indices.

Request

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GET /_searchable_snapshots/cache/stats

GET /_searchable_snapshots/<node_id>/cache/stats

Prerequisites

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If the Elasticsearch security features are enabled, you must have the manage cluster privilege to use this API. For more information, see Security privileges.

Path parameters

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<node_id>
(Optional, string) The names of particular nodes in the cluster to target. For example, nodeId1,nodeId2. For node selection options, see Node specification.

Query parameters

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master_timeout
(Optional, time units) Period to wait for the master node. If the master node is not available before the timeout expires, the request fails and returns an error. Defaults to 30s. Can also be set to -1 to indicate that the request should never timeout.

Response body

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nodes

(object) Contains statistics for the nodes selected by the request.

Properties of nodes
<node_id>

(object) Contains statistics for the node with the given identifier.

Properties of <node_id>
shared_cache

(object) Contains statistics about the shared cache file.

Properties of shared_cache
reads
(long) Number of times the shared cache is used to read data from.
bytes_read_in_bytes
(long) The total of bytes read from the shared cache.
writes
(long) Number of times data from the blob store repository is written in the shared cache.
bytes_written_in_bytes
(long) The total of bytes written in the shared cache.
evictions
(long) Number of regions evicted from the shared cache file.
num_regions
(integer) Number of regions in the shared cache file.
size_in_bytes
(long) The total size in bytes of the shared cache file.
region_size_in_bytes
(long) The size in bytes of a region in the shared cache file.

Examples

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Gets the statistics about the shared cache for partially mounted indices from all data nodes:

response = client.searchable_snapshots.cache_stats
puts response
GET /_searchable_snapshots/cache/stats

The API returns the following response:

{
  "nodes" : {
    "eerrtBMtQEisohZzxBLUSw" : {
      "shared_cache" : {
        "reads" : 6051,
        "bytes_read_in_bytes" : 5448829,
        "writes" : 37,
        "bytes_written_in_bytes" : 1208320,
        "evictions" : 5,
        "num_regions" : 65536,
        "size_in_bytes" : 1099511627776,
        "region_size_in_bytes" : 16777216
      }
    }
  }
}