.. Licensed to the Apache Software Foundation (ASF) under one
   or more contributor license agreements.  See the NOTICE file
   distributed with this work for additional information
   regarding copyright ownership.  The ASF licenses this file
   to you under the Apache License, Version 2.0 (the
   "License"); you may not use this file except in compliance
   with the License.  You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing,
   software distributed under the License is distributed on an
   "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   KIND, either express or implied.  See the License for the
   specific language governing permissions and limitations
   under the License.

.. include:: ../../../../common.defs

.. _admin-stats-core-cache:

Cache
*****

.. ts:stat:: global proxy.node.cache.bytes_free integer

   The difference between :ts:stat:`proxy.process.cache.bytes_total` and
   :ts:stat:`proxy.process.cache.bytes_used`.

   Represents the amount of space allocated to the cache which is not currently
   in use by objects.

.. ts:stat:: global proxy.node.cache.bytes_free_mb integer

   The value of :ts:stat:`proxy.node.cache.bytes_free` expressed in megabytes.

.. ts:stat:: global proxy.node.cache.bytes_total integer

   The total number of bytes allocated to the cache.

.. ts:stat:: global proxy.node.cache.bytes_total_mb integer

   The value of :ts:stat:`proxy.node.cache.bytes_total` expressed in megabytes.

.. ts:stat:: global proxy.node.cache.contents.num_docs integer
   :ungathered:

   Represents the number of documents currently residing in the cache.

.. ts:stat:: global proxy.node.cache_hit_mem_ratio_avg_10s float

   Represents the ratio of cache lookups over the previous 10 seconds which
   have been satisfied by the in-memory cache, thus avoiding disk cache I/O.

.. ts:stat:: global proxy.node.cache_hit_mem_ratio float

   Represents the ratio of cache lookups which have been satisfied by the
   in-memory cache since statistics collection began.

.. ts:stat:: global proxy.node.cache_hit_ratio_avg_10s float

   Represents the ratio of cache lookups over the previous 10 seconds which
   have been satisfied by either the in-memory cache or the disk cache, thus
   avoiding revalidation or object retrieval from origin servers.

.. ts:stat:: global proxy.node.cache_hit_ratio float

   Represents the ratio of cache lookups which have been satisfied by either the
   in-memory cache or the on-disk cache since statistics collection began.

.. ts:stat:: global proxy.node.cache.percent_free float

   Represents the percentage of allocated cache space which is not occupied by
   cache objects.

.. ts:stat:: global proxy.node.cache_total_hits_avg_10s float
.. ts:stat:: global proxy.node.cache_total_hits counter

   Represents the total number of cache lookups which have been satisfied by
   either the in-memory cache or the on-disk cache, since statistics collection
   began.

.. ts:stat:: global proxy.node.cache_total_hits_mem_avg_10s float
.. ts:stat:: global proxy.node.cache_total_hits_mem counter

   Represents the total number of cache lookups which have been satisfied by the
   in-memory cache, since statistics collection began.

.. ts:stat:: global proxy.node.cache_total_misses_avg_10s float
.. ts:stat:: global proxy.node.cache_total_misses counter

   Represents the total number of cache lookups which could not be satisfied by
   either the in-memory cache or the on-disk cache, and which required origin
   server revalidation or retrieval.

.. ts:stat:: global proxy.node.http.cache_current_connections_count integer
.. ts:stat:: global proxy.node.http.cache_hit_fresh_avg_10s float
.. ts:stat:: global proxy.node.http.cache_hit_ims_avg_10s float
.. ts:stat:: global proxy.node.http.cache_hit_mem_fresh_avg_10s float
.. ts:stat:: global proxy.node.http.cache_hit_revalidated_avg_10s float
.. ts:stat:: global proxy.node.http.cache_hit_stale_served_avg_10s float
.. ts:stat:: global proxy.node.http.cache_miss_changed_avg_10s float
.. ts:stat:: global proxy.node.http.cache_miss_client_no_cache_avg_10s float
.. ts:stat:: global proxy.node.http.cache_miss_cold_avg_10s float
.. ts:stat:: global proxy.node.http.cache_miss_ims_avg_10s float
.. ts:stat:: global proxy.node.http.cache_miss_not_cacheable_avg_10s float
.. ts:stat:: global proxy.node.http.cache_read_error_avg_10s float
.. ts:stat:: global proxy.process.cache.bytes_total integer
.. ts:stat:: global proxy.process.cache.bytes_used integer
.. ts:stat:: global proxy.process.cache.directory_collision integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.direntries.total integer
.. ts:stat:: global proxy.process.cache.direntries.used integer
.. ts:stat:: global proxy.process.cache.evacuate.active integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.evacuate.failure integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.evacuate.success integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.frags_per_doc.1 integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.frags_per_doc.2 integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.frags_per_doc.3+ integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.gc_bytes_evacuated integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.gc_frags_evacuated integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.hdr_marshal_bytes integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.hdr_marshals integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.KB_read_per_sec float
.. ts:stat:: global proxy.process.cache.KB_write_per_sec float
.. ts:stat:: global proxy.process.cache.lookup.active integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.lookup.failure integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.lookup.success integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.percent_full integer
.. ts:stat:: global proxy.process.cache.pread_count integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.ram_cache.bytes_used integer
.. ts:stat:: global proxy.process.cache.ram_cache.hits integer
.. ts:stat:: global proxy.process.cache.ram_cache.misses integer
.. ts:stat:: global proxy.process.cache.ram_cache.total_bytes integer
.. ts:stat:: global proxy.process.cache.read.active integer
.. ts:stat:: global proxy.process.cache.read_busy.failure integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.read_busy.success integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.read.failure integer
.. ts:stat:: global proxy.process.cache.read_per_sec float
.. ts:stat:: global proxy.process.cache.read.success integer
.. ts:stat:: global proxy.process.cache.remove.active integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.remove.failure integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.remove.success integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.scan.active integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.scan.failure integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.scan.success integer
   :ungathered:

.. ts:stat:: global proxy.process.cache.update.active integer
.. ts:stat:: global proxy.process.cache.update.failure integer
.. ts:stat:: global proxy.process.cache.update.success integer
.. ts:stat:: global proxy.process.cache.vector_marshals integer
.. ts:stat:: global proxy.process.cache.write.active integer
.. ts:stat:: global proxy.process.cache.write.backlog.failure integer
.. ts:stat:: global proxy.process.cache.write_bytes_stat integer
.. ts:stat:: global proxy.process.cache.write.failure integer
.. ts:stat:: global proxy.process.cache.write_per_sec float
.. ts:stat:: global proxy.process.cache.write.success integer

.. ts:stat:: global proxy.process.cache.span.errors.read integer

   The number of span read errors (counter).

.. ts:stat:: global proxy.process.cache.span.errors.write integer

   The number of span write errors (counter).

.. ts:stat:: global proxy.process.cache.span.failing integer

   The number of failing spans (gauge) - errors > 0 && errors < `proxy.config.cache.max_disk_errors`.

   `proxy.process.cache.span.failing` + `proxy.process.cache.span.offline` + `proxy.process.cache.span.online` = total number of spans.

.. ts:stat:: global proxy.process.cache.span.offline integer

   The number of offline spans (gauge) - errors >= `proxy.config.cache.max_disk_errors`.

   `proxy.process.cache.span.failing` + `proxy.process.cache.span.offline` + `proxy.process.cache.span.online` = total number of spans.

.. ts:stat:: global proxy.process.cache.span.online integer

   The number of online spans (gauge) - errors == 0.

   `proxy.process.cache.span.failing` + `proxy.process.cache.span.offline` + `proxy.process.cache.span.online` = total number of spans.


.. ts:stat:: global proxy.process.http.background_fill_bytes_aborted_stat integer
   :ungathered:

.. ts:stat:: global proxy.process.http.background_fill_bytes_completed_stat integer
   :ungathered:

.. ts:stat:: global proxy.process.http.background_fill_current_count integer
   :ungathered:

.. ts:stat:: global proxy.process.http.cache_deletes integer
.. ts:stat:: global proxy.process.http.cache_hit_fresh integer
.. ts:stat:: global proxy.process.http.cache_hit_ims integer
.. ts:stat:: global proxy.process.http.cache_hit_mem_fresh integer
.. ts:stat:: global proxy.process.http.cache_hit_revalidated integer
.. ts:stat:: global proxy.process.http.cache_hit_stale_served integer
.. ts:stat:: global proxy.process.http.cache_lookups integer
.. ts:stat:: global proxy.process.http.cache_miss_changed integer
.. ts:stat:: global proxy.process.http.cache_miss_client_no_cache integer
.. ts:stat:: global proxy.process.http.cache_miss_client_not_cacheable integer
.. ts:stat:: global proxy.process.http.cache_miss_cold integer
.. ts:stat:: global proxy.process.http.cache_miss_ims integer
.. ts:stat:: global proxy.process.http.cache_read_error integer
.. ts:stat:: global proxy.process.http.cache_read_errors integer
.. ts:stat:: global proxy.process.http.cache_updates integer
.. ts:stat:: global proxy.process.http.cache_write_errors integer
.. ts:stat:: global proxy.process.http.cache_writes integer
.. ts:stat:: global proxy.process.http.tcp_client_refresh_count_stat integer
   :ungathered:

.. ts:stat:: global proxy.process.http.tcp_client_refresh_origin_server_bytes_stat integer
   :ungathered:

.. ts:stat:: global proxy.process.http.tcp_client_refresh_user_agent_bytes_stat integer
   :ungathered:

.. ts:stat:: global proxy.process.http.tcp_expired_miss_count_stat integer
   :ungathered:

.. ts:stat:: global proxy.process.http.tcp_expired_miss_origin_server_bytes_stat integer
   :ungathered:

.. ts:stat:: global proxy.process.http.tcp_expired_miss_user_agent_bytes_stat integer
   :ungathered:

.. ts:stat:: global proxy.process.http.tcp_hit_count_stat integer
.. ts:stat:: global proxy.process.http.tcp_hit_origin_server_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_hit_user_agent_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_ims_hit_count_stat integer
.. ts:stat:: global proxy.process.http.tcp_ims_hit_origin_server_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_ims_hit_user_agent_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_ims_miss_count_stat integer
.. ts:stat:: global proxy.process.http.tcp_ims_miss_origin_server_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_ims_miss_user_agent_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_miss_count_stat integer
.. ts:stat:: global proxy.process.http.tcp_miss_origin_server_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_miss_user_agent_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_refresh_hit_count_stat integer
.. ts:stat:: global proxy.process.http.tcp_refresh_hit_origin_server_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_refresh_hit_user_agent_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_refresh_miss_count_stat integer
.. ts:stat:: global proxy.process.http.tcp_refresh_miss_origin_server_bytes_stat integer
.. ts:stat:: global proxy.process.http.tcp_refresh_miss_user_agent_bytes_stat integer