Recent Posts by Vineeth Mohan

Vineeth Mohan is a certified Elasticsearch trainer and author of "Elasticsearch Blueprints" book.

In this guide, we explore Refresh and Flush operations in Elasticsearch. This guide will bring resolution to the differences between the two in an effective manner. We also cover the underlying basics of Lucene functionalities, like reopen and commits, which helps in understanding refresh and flush operations.

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In this tutorial, we cover a few common issues related to shard management in Elasticsearch, their solutions, and several best practices. In some use cases, we incorporate special tricks to get things done. 

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Slow Logs in Elasticsearch

Posted by Vineeth Mohan January 16, 2018

In this blog post, we explore slow logs in Elasticsearch, which are immensely helpful both in production and debugging environments. We show how slow logs generated by Elasticsearch can be a critical information provider regarding numerous events and issues happening in your Elasticsearch cluster.

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In this blog post, we will cover an important feature, the filtering of values with partitions in terms aggregation, which can also be used to navigate through the unique terms in the buckets of terms aggregation.

Prior to 5.2, there was an option to put zero as value for size in terms aggregation and fetch all terms. But this approach was a failure because it could harm the main memory while downloading entire set of terms.

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In this blog post, we show how the Suggest API in Elasticsearch can handle misspelled words using the terms suggester. We also explore various implementations of the term suggester API in Elasticsearch > 6.0

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Phrase suggester is an advanced version of the term suggester. The additional functionality, which phrase suggester employs, is the selection of entire corrected phrases instead of individual words. This is based on the ngram-language modeling, and phrase suggesters can make better choices of tokens based on both frequency and concurrency.

In this tutorial, we'll show you how to use the phrase suggester to correct spellings in phrases, which offers  "did you mean" search functionality in Elasticsearch.

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The Suggest API is one of the most developed APIs in Elasticsearch. It is extensively used in search solutions which tremendously improve user experience. Ranging from normal autocomplete to context based suggestions, this API has many interesting use cases, which we are going to explore. In this tutorial, we are going to show how to implement a simple autocomplete with Elasticsearch.

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Sometimes, when firing a query, it gets delayed, or the response time is slow. There could be a number of reasons for the sluggishness of the query ranging from shard issues to time needed to compute certain elements in the query. Since version 2.2., Elasticsearch provides the Profile API for users to inspect the query execution time and other details. In this blog post, we explore how the profile API can be used to look into query timings. For this tutorial, Elasticsearch 5.0 version was used. 

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In this blog post, we are going to explain Elasticsearch memory settings in detail. These settings can be used to improve Elasticsearch performance, especially during the heavy load times and application scaling. We also go over issues caused by poor memory settings, and the ways to fix them.  

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Are you looking for full-text search and highlight capability on .PDF, .doc, or .epub files in your system? In this tutorial, we'll show you how to achieve this with the Elasticsearch mapper-attachment-plugin.

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