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With Swarm 16.1.4 and Gateway 8.1.0 we introduced a new feature called “Index per Domain”, this means within our Elasticsearch database we will now store metadata from each domain in separate indices. It is enabled by setting search.perDomainIndex=True before creating a Search Feed.
Data in Elasticsearch is organized into indices. Each index is made up of one or more shards. Each shard is an instance of a Lucene index, which you can think of as a self-contained search engine that indexes and handles queries for a subset of the data in an Elasticsearch cluster.
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