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<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>What's new in Elasticsearch 2.0</title>
<meta name="description" content="What's new in Elasticsearch 2.0">
<meta name="author" content="Igor Motov">
<meta name="apple-mobile-web-app-capable" content="yes" />
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<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no, minimal-ui">
<link rel="stylesheet" href="css/reveal.css">
<link rel="stylesheet" href="css/theme/es.css" id="theme">
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<script>
var link = document.createElement( 'link' );
link.rel = 'stylesheet';
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</head>
<body>
<div class="reveal">
<!-- Any section element inside of this container is displayed as a slide -->
<div class="slides">
<section data-background="images/esbackground.png" data-state="eslogo">
<h2>What's new in Elasticsearch 2.0</h2>
<p>
<small><a href="https://github.com/imotov">Igor Motov</a> / <a href="http://twitter.com/imotov">@imotov</a></small>
</p>
</section>
<section>
<section>
<h3>About Me</h3>
<ul>
<li>Software Developer at Elastic</li>
<li>Joined: Oct 2012</li>
<li>Elasticsearch contributor since Apr 2011</li>
</ul>
</section>
<section>
<h3>About Elastic</h3>
<ul>
<li>Founded: July 2012</li>
<li>Renamed Elasticsearch → Elastic: Mar 2015</li>
<li>Headquaters: Amsterdam and Mountain View, CA</li>
<li>Develops Elasticsearch, Logstash, Kibana, Beats</li>
<li>Provides:
<ul>
<li>Training (public and onsite)</li>
<li>Development and production support</li>
<li>Hosted Elasticsearch (Found)</li>
<li>Commercial plugins: Marvel, Shield, Watcher</li>
</ul>
</li>
</ul>
</section>
<section>
<h3>About Elasticsearch</h3>
<p>
<iframe src="//www.youtube.com/embed/sKnkQSec1U0" style="width: 580px; height: 326.25px;">
</iframe>
</p>
</section>
<section>
<h3>About Elasticsearch</h3>
<ul>
<li>Realtime search and analytics engine
<ul>
<li>JSON-oriented, Apache Lucene-based</li>
</ul>
</li>
<li>Automatic Schema Detection
<ul>
<li>With full control of schema when needed</li>
</ul>
</li>
<li>Distributed
<ul>
<li>Scales Up+Out, Highly Available</li>
</ul>
</li>
<li>Multi-tenancy
<ul>
<li>Dynamically create/delete indices</li>
</ul>
</li>
<li>API centric
<ul>
<li>Most functionalty is exposed throught an API</li>
</ul>
</li>
</ul>
</section>
</section>
<!-- Example of nested vertical slides -->
<section>
<section>
<h2>Elasticsearch 2.0</h2>
<p>Very large release</p>
<p>>2,500 Pull Requests</p>
<p>469 commiters</p>
</section>
<section>
<h3>Focus on growing up</h3>
<img src="images/growingup.jpg">
</section>
<section>
<h3>Focus on growing up</h3>
<ul>
<li>Simplification</li>
<li>Security</li>
<li>Resiliency</li>
<li>Features</li>
<li>Plugins</li>
</ul>
</section>
</section>
<section>
<section>
<h2>Simplification</h2>
<h3>sometimes includes removing stuff</h3>
<img src="images/trash.jpg" alt="trash">
</section>
<section>
<h3>What’s NOT in Elasticsearch 2.0</h3>
<ul>
<li class="fragment">Rivers<span class="fragment"><i> - use logstash or invest into your own ingestion layer</i></span></li>
<li class="fragment">Facets<span class="fragment"><i> - replaced by aggregations</i></span></li>
<li class="fragment">_shutdown API<span class="fragment"><i> - use platform specific services</i></span></li>
<li class="fragment">Support for Thrift and Memcached protocols</li>
<li class="fragment">Bulk UDP <span class="fragment"><i> - use the standard bulk API, or use UDP to send documents to Logstash first.</i></span></li>
</ul>
</section>
<section>
<h3>What’s NOT in Core</h3>
<h3>(Moved to a plugin)</h3>
<ul>
<li>Delete by query</li>
<li>Types:
<ul>
<li>murmur3</li>
<li>size</li>
</ul>
</li>
<li>Multicast discovery</li>
</ul>
</section>
</section>
<section>
<section>
<h2>Simplification: Mapping changes</h2>
<img src="images/map2.jpg" alt="map">
</section>
<section>
<h2>Simplification: Mapping changes</h2>
<ul>
<li>Conflicting field mappings</li>
<li>Fields cannot be referenced by short name</li>
<li>Type name prefix removed</li>
<li>Field names cannot contain dots</li>
<li>Type names cannot start with a dot</li>
<li>Type may no longer be deleted</li>
<li><code>index_analyzer</code> is removed</li>
<li><code>_analyzer</code> field is removed</li>
<li>date format changes</li>
<li>... and more ...</li>
</ul>
<aside class="notes">
This is a big one. See <a href="https://www.elastic.co/blog/great-mapping-refactoring">this blog post</a> for details.
</aside>
</section>
<section>
<h3>Conflicting field mapping</h3>
<pre><code class="json">PUT my_index
{
"mappings": {
"type_one": {
"properties": {
"name": { "type": "string" } ❶
}
},
"type_two": {
"properties": {
"name": { "type": "string", "analyzer": "english" } ❷
}
}
}
}</code></pre>
<aside class="notes">
This was acceptable before 2.0 but was producing unexpected results. In 2.0 this mapping is no longer valid.
</aside>
</section>
<section>
<h3>Ambiguous field lookup before 2.0</h3>
<pre><code class="json">PUT my_index
{
"mappings": {
"name": { ❶
"properties": {
"title": { "type": "string" }, ❷
"name": { ❸
"properties": {
"title": { "type": "string" } ❹
}
}
}
}
}
}</code></pre>
<p>What does <code>title</code> refer to?</p>
<p class="fragment">What about <code>name.title</code>?</p>
<p class="fragment">What about <code>name.name.title</code>?</p>
</section>
<section>
<h3>Field lookup in 2.0</h3>
<pre><code class="json">PUT my_index
{
"mappings": {
"name": { ❶
"properties": {
"title": { "type": "string" }, ❷
"name": { ❸
"properties": {
"title": { "type": "string" } ❹
}
}
}
}
}
}</code></pre>
<p>"<code>title</code>" always refers to ❷</p>
<p>"<code>name.title</code>" always refers to ❹</p>
<p>"<code>name.name.title</code>" is invalid</p>
</section>
<section>
<h3>Field analyzer</h3>
<pre><code class="json">PUT my_index
{
"mappings": {
"my_type": {
"properties": {
"title": { "type": "string", "analyzer": "my_analyzer }
}
}
}
}</code></pre>
<aside class="notes">
There are some changes in how field-specific analyzer is now set. This format, which sets both
search and index analyzers is still acceptable in 2.0.
</aside>
</section>
<section>
<h3>Field analyzer</h3>
<p>Before 2.0:</p>
<ul>
<li><code>analyzer</code> - sets <b>index</b> and <b>search</b> analyzers</li>
<li><code>search_analyzer</code> - sets <b>search</b> analyzer</li>
<li><code>index_analyzer</code> - sets <b>index</b> analyzer</li>
</ul>
<p>Starting with 2.0:</p>
<ul>
<li><code>analyzer</code> - sets <b>index</b> and <b>search</b> analyzers</li>
<li><code>search_analyzer</code> - overrides <b>search</b> analyzer</li>
</ul>
<aside class="notes">
But if you want different analyzers - there are some changes.
</aside>
</section>
<section>
<h3>Other Mapping Changes</h3>
<p>Check <a href="https://www.elastic.co/blog/great-mapping-refactoring">The Great Mapping Refactoring</a> blog post </p>
<img src="images/map.jpg" alt="map">
</section>
</section>
<section>
<section>
<h2>Simplification: Query and Filter Execution Changes</h2>
</section>
<section>
<h3>Before 2.0</h3>
<dl>
<dt>Queries:</dt>
<dd>
<ul>
<li>Typically contribute to scoring</li>
<li>No caching</li>
</ul>
</dd>
<dt>Filters:</dt>
<dd>
<ul>
<li>Don't contribute to scoring</li>
<li>Can be cached</li>
</ul>
</dd>
</dl>
<aside class="notes">
</aside>
</section>
<section>
<h3>Starting with 2.0</h3>
<ul>
<li>Filters and queries are merged into queries</li>
<li>The behavior of a query clause depends on whether it is used in query context or in filter context</li>
</ul>
</section>
<section>
<h3>Before 2.0</h3>
<pre><code class="json">{
"filtered" : {
"query": { query definition },
"filter": { filter definition }
}
}</code></pre>
<h3>Starting with 2.0</h3>
<pre><code class="json">{
"bool" : {
"must": { query definition },
"filter": { filter definition }
}
}</code></pre>
</section>
<section>
<h3>Two-phase execution</h3>
<dl>
<dt>Approximation phase</dt>
<dd>quickly iterates over a superset of the matching documents</dd>
<dt>Verification phase</dt>
<dd>check if a document in this superset actually matches the query</dd>
</dl>
</section>
<section>
<h3>Two-phase execution - how is this useful?</h3>
<pre><code class="json">{
"bool" : {
"must": [{
"match_phrase": {
"body": "quick fox" ❶
}, {
"match_phrase": {
"body": "brown dog" ❷
}
}]
}
}</code></pre>
<p>Instead of loading posting list for all documents that contain quick and fox or brown and dog, we only load postings for the documents that contain all 4 terms.</p>
<aside class="notes">
Why is it useful? Imagine that you are searching for "quick fox" and "brown dog". The fact that we
can dissociate the approximation from the verification phase allows us to first intersect two
approximations, so that we will verify positions on a smaller set of documents.
This two-phase iteration pattern also applies to other queries: for instance geo-distance queries
can use a bounding box as an approximation and a distance computation as a verification, and filters
that only make sense in a random-access fashion such as the script filter can return all documents in
the index as an approximation and run the script as a verification.
</aside>
</section>
<section>
<h3>Query Caching</h3>
<ul>
<li>Fully automatic</li>
<li>Keeps track of 256 most recently used queries</li>
<li>Only caches those that appear 5 times or more</li>
<li>Does not cache segments which have less than 10000 documents or 3% of the documents of the index</li>
<li>More efficient query cache (roaring bitmaps)</li>
<li>Non-scoring components are cache-able</li>
</ul>
</section>
</section>
<section>
<section>
<h2>Security</h2>
<img src="images/security.jpg" alt="security">
</section>
<section>
<h3>Networking changes</h3>
<p>Elasticsearch now binds to local interfaces</p>
<p>Unicast discovery is now default</p>
<p>Makes elasticsearch more secure by default</p>
<aside class="notes">
This was done for security reasons. Many elasticsearch instances are running in the open. See <a href="https://www.elastic.co/blog/elasticsearch-unplugged">this blog post</a> for more information
</aside>
</section>
<section>
<h3>Running under security manager by default</h3>
<ul>
<li>Prevents outside access outside of elasticsearch even if elasticsearch process is compromised</li>
<li>All resources that elasticsearch can access are defined on node startup</li>
<li>Some libs/plugins are unsecured!</li>
</ul>
</section>
</section>
<section>
<section>
<h2>Reliability</h2>
</section>
<section>
<h3>Index operations are now durable by default</h3>
<ul>
<li>Before 2.0 transaction log was fsynced every 5 sec</li>
<li>Transaction log is now fsync after each operation</li>
<li>Configurable</li>
<li>On SSDs have indexing is about 7% - 10% slower with bulk indexing compared to async translog flushes</li>
</ul>
</section>
<section>
<h3>Multiple data path striping</h3>
<ul>
<li>Before all shards were stripped across all paths</li>
<li>This striping is no longer supported. Instead, different shards may be allocated to different paths, but all of the files in a single shard will be written to the same path.</li>
</ul>
</section>
<section>
<h3>Multiple data path striping</h3>
<img src="images/striping0.png">
</section>
<section>
<h3>Before 2.0</h3>
<img src="images/striping1.png">
</section>
<section>
<h3>After 2.0</h3>
<img src="images/striping2.png">
</section>
<section>
<h3>Cluster State Diffs</h3>
<ul>
<li>Before entire cluster state was shipped on every change to every node</li>
<li>Starting with 2.0 only changes are sent</li>
</ul>
</section>
<section>
<h3>Units are required in all settings</h3>
<pre><code class="json">curl -XPUT "localhost:9200/test/_settings" -d '{
"index" : {
"refresh_interval" : "5"
}
}'</code></pre>
<p>What have I just done here?</p>
</section>
<section>
<h3>Doc values by default</h3>
<ul>
<li>Dramatic memory-reduction by default</li>
<li>Any field that is indexed but not analyzed now has doc values.</li>
<li>Only for indices created with 2.0</li>
</ul>
</section>
<section>
<h3>Some cool recent reliability changes that you might have missed</h3>
<ul>
<li>Sync-flush with <code>sync_id</code> (1.6)</li>
<li>Async shard allocation (1.6) <i>was blocking cluster state</i></li>
<li>Better handling of node leave/rejoin (1.7) <i>wait for one minute</i></li>
</ul>
</section>
</section>
<section>
<section>
<h2>Features</h2>
<img src="images/features.jpg" alt="features">
</section>
<section>
<h3>Pipeline aggs</h3>
<ul>
<li>Derivatives</li>
<li>Moving average</li>
<li>Holt Winters (prediction / anomaly detection)</li>
<li>Stats: Min/Max/avg</li>
<li>Time-series math</li>
</ul>
<aside class="notes">
We might do another presentation devoted to new agg features.
See <a href="https://www.elastic.co/blog/out-of-this-world-aggregations">this blog post for details</a>
</aside>
</section>
<section>
<h3>Moving average - 10</h3>
<img src="images/movavg_10window.png" alt="Moving average">
</section>
<section>
<h3>Moving average - 100</h3>
<img src="images/movavg_100window.png" alt="Moving average">
</section>
<section>
<h3>Holt Winters - seasonal fluctuations</h3>
<img src="images/triple_prediction.png" alt="Holt Winters">
</section>
<section>
<h3>Index compression</h3>
<ul>
<li>10-30% reduction in index size</li>
<li>Some indexing/merging impact</li>
<li>Dynamic setting - could be set before optimization for time-based indices</li>
</ul>
</section>
</section>
<section>
<section>
<h2>Plugins</h2>
<img src="images/plugins.jpg" alt="plugins">
</section>
<section>
<pre><code class="shell">$ mvn clean install</code></pre>
<pre><code class="shell">[INFO] Plugin: Analysis: ICU .............................. SUCCESS
[INFO] Plugin: Analysis: Japanese (kuromoji) .............. SUCCESS
[INFO] Plugin: Analysis: Phonetic ......................... SUCCESS
[INFO] Plugin: Analysis: Smart Chinese (smartcn) .......... SUCCESS
[INFO] Plugin: Analysis: Polish (stempel) ................. SUCCESS
[INFO] Plugin: Delete By Query ............................ SUCCESS
[INFO] Plugin: Discovery: Azure ........................... SUCCESS
[INFO] Plugin: Discovery: EC2 ............................. SUCCESS
[INFO] Plugin: Discovery: Google Compute Engine ........... SUCCESS
[INFO] Plugin: Discovery: Multicast ....................... SUCCESS
[INFO] Plugin: Language: Expression ....................... SUCCESS
[INFO] Plugin: Language: Groovy ........................... SUCCESS
[INFO] Plugin: Language: JavaScript ....................... SUCCESS
[INFO] Plugin: Language: Python ........................... SUCCESS
[INFO] Plugin: Mapper: Murmur3 ............................ SUCCESS
[INFO] Plugin: Mapper: Size ............................... SUCCESS
[INFO] Plugin: Repository: Azure .......................... SUCCESS
[INFO] Plugin: Repository: S3 ............................. SUCCESS
[INFO] Plugin: Store: SMB ................................. SUCCESS</code></pre>
</section>
<section>
<h3>Before 2.0</h3>
<pre><code class="nohighlight">$ bin/plugin install elasticsearch/cloud-aws/2.7.2
$ bin/plugin install cloud-aws --url http://p.to/cloud-aws-2.7.2.zip
$ bin/plugin install cloud-aws --url file:p/to/cloud-aws-2.7.2.zip</code></pre>
<h3>Starting with 2.0</h3>
<pre><code class="nohighlight">$ bin/plugin install cloud-aws
$ bin/plugin install http://p.to/cloud-aws-2.7.2.zip
$ bin/plugin install file:p/to/cloud-aws-2.7.2.zip</code></pre>
</section>
</section>
<section>
<section>
<h2>Migration Process</h2>
<img src="images/passports.jpg" alt="passports">
</section>
<section>
<h3>2.0 is a major release</h3>
<ul>
<li>No rolling upgrades</li>
<li>One way - no way to downgrade back to 1.x</li>
<li>Make sure you have a backup</li>
<li>Test it! Don't try to "wing it" in production.</li>
</ul>
<img src="images/danger.jpg" alt="danger">
</section>
<section>
<h3>Migration plugin</h3>
<ul>
<li>Site plugin for 1.x that checks for potential issues</li>
<li><a href="https://github.com/elastic/elasticsearch-migration">https://github.com/elastic/elasticsearch-migration</a></li>
</ul>
<img src="images/migration.png" alt="migration">
</section>
<section>
<h3>Getting help</h3>
<ul>
<li><a href="https://discuss.elastic.co/" target="_blank">https://discuss.elastic.co/</a> - Discussion Forums</li>
<li><a href="https://github.com/elastic/elasticsearch" target="_blank">https://github.com/elastic/elasticsearch</a> - Report issues</li>
<li>IRC on Freenode - #elasticsearch</li>
<li><a href="http://stackoverflow.com/questions/tagged/elasticsearch" target="_blank">http://stackoverflow.com/questions/tagged/elasticsearch</a></li>
</ul>
<aside class="notes">
Stackoverflow - good for general questions, not so good for online troubleshooting
</ul>
</aside>
</section>
</section>
<section>
<section>
<h3>elastic{ON} TOUR</h3>
<ul>
<li>Amsterdam - Oct 29</li>
<li>London - Nov 3</li>
<li>Paris - Nov 5</li>
<li>München - Nov 10</li>
<li>New York - Nov 17</li>
<li>Chicago - Nov 19</li>
<li>Los Angeles - Dec 1</li>
<li>Seattle - Dec 3</li>
<li>Sydney - Dec 8</li>
<li>Melbourne - Dec 10</li>
<li>Tokyo - Dec 16</li>
</ul>
</section>
<section>
<h3>elastic{ON} <sup>'16</sup></h3>
<ul>
<li>Feb 17-19, 2016</li>
<li>Pier 48, San Francisco, CA</li>
<li>Last year, Elastic{ON} sold out in just one week.</li>
<li><a href="https://www.elastic.co/elasticon" target="_blank">https://www.elastic.co/elasticon</a></li>
</ul>
</section>
</section>
<section style="text-align: left;">
<h1>THE END</h1>
<ul>
<li>Slides: <a href="https://imotov.github.io/presentations" target="_blank">https://imotov.github.io/presentations</a></li>
<li>Twitter: <a href="https://twitter.com/imotov" target="_blank">@imotov</a></li>
</ul>
</section>
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