[role="xpack"]
[[searchable-snapshots-api-cache-stats]]
=== Cache stats API
++++
<titleabbrev>Cache stats</titleabbrev>
++++

Retrieves statistics about the shared cache for <<partially-mounted,partially
mounted indices>>.

[[searchable-snapshots-api-cache-stats-request]]
==== {api-request-title}

`GET /_searchable_snapshots/cache/stats` +

`GET /_searchable_snapshots/<node_id>/cache/stats`

[[searchable-snapshots-api-cache-stats-prereqs]]
==== {api-prereq-title}

If the {es} {security-features} are enabled, you must have the
`manage` cluster privilege to use this API.
For more information, see <<security-privileges>>.

[[searchable-snapshots-api-cache-stats-path-params]]
==== {api-path-parms-title}

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

[[searchable-snapshots-api-cache-stats-query-params]]
==== {api-query-parms-title}

include::{es-ref-dir}/rest-api/common-parms.asciidoc[tag=master-timeout]

[role="child_attributes"]
[[searchable-snapshots-api-cache-stats-response-body]]
==== {api-response-body-title}

`nodes`::
(object)
Contains statistics for the nodes selected by the request.
+
.Properties of `nodes`
[%collapsible%open]
====
`<node_id>`::
(object)
Contains statistics for the node with the given identifier.
+
.Properties of `<node_id>`
[%collapsible%open]
=====
`shared_cache`::
(object)
Contains statistics about the shared cache file.
+
.Properties of `shared_cache`
[%collapsible%open]
======
`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.
======
=====
====


[[searchable-snapshots-api-cache-stats-example]]
==== {api-examples-title}

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

[source,console]
--------------------------------------------------
GET /_searchable_snapshots/cache/stats
--------------------------------------------------
// TEST[setup:node]

The API returns the following response:

[source,console-result]
----
{
  "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
      }
    }
  }
}
----
// TESTRESPONSE[s/"reads" : 6051/"reads" : 0/]
// TESTRESPONSE[s/"bytes_read_in_bytes" : 5448829/"bytes_read_in_bytes" : 0/]
// TESTRESPONSE[s/"writes" : 37/"writes" : 0/]
// TESTRESPONSE[s/"bytes_written_in_bytes" : 1208320/"bytes_written_in_bytes" : 0/]
// TESTRESPONSE[s/"evictions" : 5/"evictions" : 0/]
// TESTRESPONSE[s/"num_regions" : 65536/"num_regions" : 0/]
// TESTRESPONSE[s/"size_in_bytes" : 1099511627776/"size_in_bytes" : 0/]
// TESTRESPONSE[s/"eerrtBMtQEisohZzxBLUSw"/\$node_name/]
