When Lucene and Solr searches through the data, each document is assigned a score that is calculated on the basis of query terms statistics. When using SolrCloud and our data inside the collection is distributed among multiple shards we are hit by a problem of not exact inverse document frequency calculation. The problem can be defined in the following way – each shard stores the term statistics locally and doesn’t share that with other shards during query execution. Can we do something about it to have more precise IDF calculation? Let’s see what we can do about it.
Read moreLucene and Solr 8.1.0
It is a pleasure to inform that the new version of Lucene library and Solr search server has been released. It is the next release from the 8.x branch and it is numbered 8.1.0. This release introduces fixes for the bugs found in the 8.0 version and new features.
Read moreSolr 8 – ByteBuffersDirectory – quick look
One of the new features introduced in the recently released Solr 8.0 is new implementation of the Directory interface – one that will replace not scalable RAMDirectory. The new implementation called ByteBuffersDirectory is dedicated to small, short lived data that is held only in memory. Let’s have a quick look into potential use cases, advantages and drawbacks of this new implementation.
Read moreMigration to Solr 8
With the recent release of Solr 8.0 you may be wondering if it is worth migrating to the new version and how to do it. Is it possible to upgrade your cluster without major downtime? Is it possible to upgrade to new version using rolling restarts? We will try to answer that question in this blog post.
Read moreLucene & Solr 8.0
It is a pleasure to inform that the new major release of Apache Lucene search library and Apache Solr search servers are now available. This release is numbered 8.0 and contains number of improvements and new features that should make every user consider an upgrade.
Read moreLucene & Solr 7.7.1
It is a pleasure to inform that the new version of Lucene library and Solr search server has been released. It is the next release from the 7.x branch and it is numbered 7.7.1. This release introduces fixes for the bugs found in the 7.7.1 version.
Read moreLucene and Solr 7.7.0
It is a pleasure to inform that the new version of Lucene library and Solr search server has been released. It is the next release from the 7.x branch and it is numbered 7.7.0. This release introduces fixes for the bugs found in the 7.6 version and new features.
Read moreSolrCloud and query execution control
With the release of Solr 7.0 and introduction of new replica types, in addition to the defa?ult NRT type the question appeared – can we control the queries and where they are executed? Can we tell Solr to execute the queries only on the PULL replicas or give TLOG replicas a priority? Let’s check that out.
Read moreSolrCloud – write and read tolerance
SolrCloud similar to most of the distributed systems is designed with some rules in mind. There are also rules that each distributed system is subject to. For example the CAP theorem tells that a system can’t achieve availability, data consistency and network partition split tolerance at the same time – you can have two out of three at most. Of course, in this blog entry, we will not be discussing principles of the distributed systems, but we will focus on write and read tolerance in SolrCloud.
Read moreSolr 7.6.0 – uninvertible fields
With the recent release of Solr 7.6.0 we got a new option for the fields and field types – the property called uninvertible. It allows us to control what Solr will do when it will require data in an uninverted format, so for example when using faceting or sorting. Let’s look into what happens with various settings of this new property.
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