34 lines
1.1 KiB
Plaintext
34 lines
1.1 KiB
Plaintext
[[index-modules-cache]]
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== Cache
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There are different caching inner modules associated with an index. They
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include `filter` and others.
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[float]
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[[filter]]
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=== Filter Cache
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The filter cache is responsible for caching the results of filters (used
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in the query). The default implementation of a filter cache (and the one
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recommended to use in almost all cases) is the `node` filter cache type.
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[float]
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[[node-filter]]
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==== Node Filter Cache
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The `node` filter cache may be configured to use either a percentage of
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the total memory allocated to the process or a specific amount of
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memory. All shards present on a node share a single node cache (thats
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why its called `node`). The cache implements an LRU eviction policy:
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when a cache becomes full, the least recently used data is evicted to
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make way for new data.
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The setting that allows one to control the memory size for the filter
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cache is `indices.cache.filter.size`, which defaults to `10%`. *Note*,
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this is *not* an index level setting but a node level setting (can be
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configured in the node configuration).
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`indices.cache.filter.size` can accept either a percentage value, like
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`30%`, or an exact value, like `512mb`.
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