35 lines
1.5 KiB
Plaintext
35 lines
1.5 KiB
Plaintext
[[query-cache]]
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=== Node query cache settings
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The results of queries used in the filter context are cached in the node query
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cache for fast lookup. There is one queries cache per node that is shared by all
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shards. The cache uses an LRU eviction policy: when the cache is full, the least
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recently used query results are evicted to make way for new data. You cannot
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inspect the contents of the query cache.
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Term queries and queries used outside of a filter context are not eligible for
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caching.
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By default, the cache holds a maximum of 10000 queries in up to 10% of the total
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heap space. To determine if a query is eligible for caching, {es} maintains a
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query history to track occurrences.
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Caching is done on a per segment basis if a segment contains at least 10000
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documents and the segment has at least 3% of the total documents of a shard.
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Because caching is per segment, merging segments can invalidate cached queries.
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The following setting is _static_ and must be configured on every data node in
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the cluster:
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`indices.queries.cache.size`::
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Controls the memory size for the filter cache , defaults to `10%`. Accepts
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either a percentage value, like `5%`, or an exact value, like `512mb`.
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The following setting is an _index_ setting that can be configured on a
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per-index basis. Can only be set at index creation time or on a
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<<indices-open-close,closed index>>:
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`index.queries.cache.enabled`::
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Controls whether to enable query caching. Accepts `true` (default) or
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`false`.
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