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Subject svn commit: r952022 - in /websites/staging/accumulo/trunk/content: ./ release_notes/1.7.0.html
Date Wed, 20 May 2015 12:10:03 GMT
Author: buildbot
Date: Wed May 20 12:10:02 2015
New Revision: 952022

Staging update by buildbot for accumulo

    websites/staging/accumulo/trunk/content/   (props changed)

Propchange: websites/staging/accumulo/trunk/content/
--- cms:source-revision (original)
+++ cms:source-revision Wed May 20 12:10:02 2015
@@ -1 +1 @@

Modified: websites/staging/accumulo/trunk/content/release_notes/1.7.0.html
--- websites/staging/accumulo/trunk/content/release_notes/1.7.0.html (original)
+++ websites/staging/accumulo/trunk/content/release_notes/1.7.0.html Wed May 20 12:10:02 2015
@@ -343,19 +343,12 @@ using Accumulo's public API. The regular
 <a href="">README</a>.</p>
 <h1 id="performance-improvements">Performance Improvements</h1>
 <h2 id="configurable-threadpool-size-for-assignments">Configurable Threadpool Size
for Assignments</h2>
-<p>One of the primary tasks that the Accumulo Master is responsible for is the
-assignment of tablets to tablet servers. Before a tablet can be brought
-online, it must not have any outstanding logs because this represents a need
-to perform recovery (the tablet was not unloaded cleanly). This process can
-take some time for large write-ahead log files, so it is performed on a tablet
-server to keep the Master light and agile.</p>
-<p>Assignments, whether the tablets need to perform recovery or not, share the
-same threadpool in the Master. This means that when a large number of tablet
-servers are available, too few threads dedicated to assignment can restrict
-the speed at which assignments can be performed.
-<a href="">ACCUMULO-1085</a>
allows the size of the threadpool used in the
-Master for assignments to be configurable which can be dynamically altered to
-remove the limitation when sufficient servers are available.</p>
+<p>During start-up, the Master quickly assigns tablets to Tablet Servers. However,
+Tablet Servers load those assigned tablets one at a time. In 1.7, the servers
+will be more aggressive, and will load tablets in parallel, so long as they do
+not have mutations that need to be recovered.</p>
+<p><a href="">ACCUMULO-1085</a>
allows the size of the threadpool used in the Tablet Servers 
+for assignment processing to be configurable.</p>
 <h2 id="group-commit-threshold-as-a-factor-of-data-size">Group-Commit Threshold as
a Factor of Data Size</h2>
 <p>When ingesting data into Accumulo, the majority of time is spent in the
 write-ahead log. As such, this is a common place that optimizations are added.

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