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From ktur...@apache.org
Subject [accumulo-website] branch asf-site updated: Jekyll build from master:7b25602
Date Thu, 02 Aug 2018 17:40:00 GMT
This is an automated email from the ASF dual-hosted git repository.

kturner pushed a commit to branch asf-site
in repository https://gitbox.apache.org/repos/asf/accumulo-website.git


The following commit(s) were added to refs/heads/asf-site by this push:
     new 5545c5d  Jekyll build from master:7b25602
5545c5d is described below

commit 5545c5d2d3da047c91f5dc36e43fc0a5151fedaf
Author: Keith Turner <kturner@apache.org>
AuthorDate: Thu Aug 2 13:39:29 2018 -0400

    Jekyll build from master:7b25602
    
    Add docs for scan execution hints apache/accumulo#571 (#100)
---
 docs/2.0/administration/scan-executors.html | 37 ++++++++++++++++++++++++++---
 feed.xml                                    |  4 ++--
 redirects.json                              |  2 +-
 search_data.json                            |  2 +-
 4 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/docs/2.0/administration/scan-executors.html b/docs/2.0/administration/scan-executors.html
index 36a9a58..99756b2 100644
--- a/docs/2.0/administration/scan-executors.html
+++ b/docs/2.0/administration/scan-executors.html
@@ -374,7 +374,7 @@ tserver.scan.executors.&lt;name&gt;.prioritizer.opts.&lt;key&gt;=&lt;value&gt;
 
 <p>After creating an executor, configure <a href="/docs/2.0/administration/properties#table_scan_dispatcher">table.scan.dispatcher</a>
to use it.  A
 dispatcher is Java subclass of <a href="https://static.javadoc.io/org.apache.accumulo/accumulo-core/1.9.2/org/apache/accumulo/core/spi/scan/ScanDispatcher.html">ScanDispatcher</a>
-that decides which scan executor should service a table.  Set the following table 
+that decides which scan executor should service a table.  Set the following table
 property to configure a dispatcher.</p>
 
 <div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>table.scan.dispatcher=&lt;class
name&gt;
@@ -413,12 +413,15 @@ config -s tserver.scan.executors.high.threads=8
 
 <p>Tablet servers should be restarted after configuring scan executors, then tables
can be configured.</p>
 
-<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>config
-t LOW1 -s table.scan.dispatcher.opts.executor=low
+<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>config
-t LOW1 -s table.scan.dispatcher=org.apache.accumulo.core.spi.scan.SimpleScanDispatcher
+config -t LOW1 -s table.scan.dispatcher.opts.executor=low
+config -t LOW2 -s table.scan.dispatcher=org.apache.accumulo.core.spi.scan.SimpleScanDispatcher
 config -t LOW2 -s table.scan.dispatcher.opts.executor=low
+config -t HIGH -s table.scan.dispatcher=org.apache.accumulo.core.spi.scan.SimpleScanDispatcher
 config -t HIGH -s table.scan.dispatcher.opts.executor=high
 </code></pre></div></div>
 
-<p>While not necessary because its the default, it would be safer to also set
+<p>While not necessary because its the default, it is safer to also set
 <code class="highlighter-rouge">table.scan.dispatcher=org.apache.accumulo.core.spi.scan.SimpleScanDispatcher</code>
 for each table.  This ensures things work as expected in the case where
 <code class="highlighter-rouge">table.scan.dispatcher</code> was set at the system
or namespace level.</p>
@@ -441,6 +444,34 @@ executor.</p>
 threads repeatedly doing small random lookups made a significant difference.
 In this test the average lookup time for the 5 threads went from 250ms to 5 ms.</p>
 
+<h3 id="providing-hints-from-the-client-side">Providing hints from the client side.</h3>
+
+<p>Scanners can provide hints to ScanDispatchers and ScanPriotizers by calling
+<a href="https://static.javadoc.io/org.apache.accumulo/accumulo-core/1.9.2/org/apache/accumulo/core/client/ScannerBase.html#setExecutionHints-java.util.Map-">setExecutionHints</a>
on the Scanner.  What, if anything, is done with these
+hints depends on what is configured for the table and system.  Accumulo’s
+default configuration ignores hints. The following shell commands make it
+possible to choose an executor and set priorities from a scanner for the
+table <code class="highlighter-rouge">tex</code>.</p>
+
+<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>config
-s tserver.scan.executors.special.threads=8
+config -s tserver.scan.executors.special.prioritizer=org.apache.accumulo.core.spi.scan.HintScanPrioritizer
+createtable tex
+config -t tex -s table.scan.dispatcher=org.apache.accumulo.core.spi.scan.SimpleScanDispatcher
+config -t tex -s table.scan.dispatcher.opts.heed_hints=true
+</code></pre></div></div>
+
+<p>The <a href="https://static.javadoc.io/org.apache.accumulo/accumulo-core/1.9.2/org/apache/accumulo/core/spi/scan/HintScanPrioritizer.html">HintScanPrioritizer</a>
honors
+hints of the form <code class="highlighter-rouge">priority=&lt;integer&gt;</code>
to prioritize scans, with lower integers
+resulting in a higher priority. The <code class="highlighter-rouge">SimpleScanDispatcher</code>,
which is the
+default dispatcher, supports the <code class="highlighter-rouge">heed_hints</code>
option. By default the
+<code class="highlighter-rouge">SimpleScanDispatcher</code> ignores hints, but
when <code class="highlighter-rouge">heed_hints</code> is set to <code class="highlighter-rouge">true</code>
it
+will honor hints of the form <code class="highlighter-rouge">executor=&lt;executor
name&gt;</code> when choosing an
+executor. After restarting tservers, the following command will start a scan
+that uses the executor <code class="highlighter-rouge">special</code> with a
priority of 3.</p>
+
+<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>scan
-t tex --execution-hints priority=3,executor=special
+</code></pre></div></div>
+
 
 
     <div class="row" style="margin-top: 20px;">
diff --git a/feed.xml b/feed.xml
index 7e4737f..936cb97 100644
--- a/feed.xml
+++ b/feed.xml
@@ -6,8 +6,8 @@
 </description>
     <link>https://accumulo.apache.org/</link>
     <atom:link href="https://accumulo.apache.org/feed.xml" rel="self" type="application/rss+xml"/>
-    <pubDate>Wed, 25 Jul 2018 09:24:49 -0400</pubDate>
-    <lastBuildDate>Wed, 25 Jul 2018 09:24:49 -0400</lastBuildDate>
+    <pubDate>Thu, 02 Aug 2018 13:39:23 -0400</pubDate>
+    <lastBuildDate>Thu, 02 Aug 2018 13:39:23 -0400</lastBuildDate>
     <generator>Jekyll v3.7.3</generator>
     
     
diff --git a/redirects.json b/redirects.json
index 2ec52c0..580f60e 100644
--- a/redirects.json
+++ b/redirects.json
@@ -1 +1 @@
-{"/release_notes/1.5.1.html":"https://accumulo.apache.org/release/accumulo-1.5.1/","/release_notes/1.6.0.html":"https://accumulo.apache.org/release/accumulo-1.6.0/","/release_notes/1.6.1.html":"https://accumulo.apache.org/release/accumulo-1.6.1/","/release_notes/1.6.2.html":"https://accumulo.apache.org/release/accumulo-1.6.2/","/release_notes/1.7.0.html":"https://accumulo.apache.org/release/accumulo-1.7.0/","/release_notes/1.5.3.html":"https://accumulo.apache.org/release/accumulo-1.5.3/"
[...]
\ No newline at end of file
+{"/release_notes/1.5.1.html":"https://accumulo.apache.org/release/accumulo-1.5.1/","/release_notes/1.6.0.html":"https://accumulo.apache.org/release/accumulo-1.6.0/","/release_notes/1.6.1.html":"https://accumulo.apache.org/release/accumulo-1.6.1/","/release_notes/1.6.2.html":"https://accumulo.apache.org/release/accumulo-1.6.2/","/release_notes/1.7.0.html":"https://accumulo.apache.org/release/accumulo-1.7.0/","/release_notes/1.5.3.html":"https://accumulo.apache.org/release/accumulo-1.5.3/"
[...]
\ No newline at end of file
diff --git a/search_data.json b/search_data.json
index 588cb58..b844660 100644
--- a/search_data.json
+++ b/search_data.json
@@ -65,7 +65,7 @@
   
     "docs-2-0-administration-scan-executors": {
       "title": "Scan Executors",
-      "content"	 : "Accumulo scans operate by repeatedly fetching batches of data from a
tabletserver.  On the tablet server side, a thread pool fetches batches.In Java threads pools
are called executors.  By default, a single executor pertablet server handles all scans in
FIFO order.  For some workloads, the singleFIFO executor is suboptimal.  For example, consider
many unimportant scansreading lots of data mixed with a few important scans reading small
amounts ofdata.  The long scans n [...]
+      "content"	 : "Accumulo scans operate by repeatedly fetching batches of data from a
tabletserver.  On the tablet server side, a thread pool fetches batches.In Java threads pools
are called executors.  By default, a single executor pertablet server handles all scans in
FIFO order.  For some workloads, the singleFIFO executor is suboptimal.  For example, consider
many unimportant scansreading lots of data mixed with a few important scans reading small
amounts ofdata.  The long scans n [...]
       "url": " /docs/2.0/administration/scan-executors",
       "categories": "administration"
     },


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