accumulo-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From build...@apache.org
Subject svn commit: r951780 - in /websites/staging/accumulo/trunk/content: ./ release_notes/1.7.0.html
Date Mon, 18 May 2015 20:29:48 GMT
Author: buildbot
Date: Mon May 18 20:29:48 2015
New Revision: 951780

Log:
Staging update by buildbot for accumulo

Modified:
    websites/staging/accumulo/trunk/content/   (props changed)
    websites/staging/accumulo/trunk/content/release_notes/1.7.0.html

Propchange: websites/staging/accumulo/trunk/content/
------------------------------------------------------------------------------
--- cms:source-revision (original)
+++ cms:source-revision Mon May 18 20:29:48 2015
@@ -1 +1 @@
-1680087
+1680088

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 Mon May 18 20:29:48 2015
@@ -316,16 +316,29 @@ be relaxed, such as when power is redund
 <h3 id="wait-for-tablet-balance-api">Wait for tablet balance API</h3>
 <p>https://issues.apache.org/jira/browse/ACCUMULO-2998</p>
 <h2 id="notable-bug-fixes">Notable Bug Fixes</h2>
-<h3 id="bug-fix-1">Bug Fix 1</h3>
-<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt
ut labore et dolore magna aliqua.
-Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea
commodo consequat. Duis aute irure
- dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur
sint occaecat cupidatat
- non proident, sunt in culpa qui officia deserunt mollit anim id est laborum</p>
-<h3 id="bug-fix-2">Bug Fix 2</h3>
-<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt
ut labore et dolore magna aliqua.
-Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea
commodo consequat. Duis aute irure
- dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur
sint occaecat cupidatat
- non proident, sunt in culpa qui officia deserunt mollit anim id est laborum</p>
+<h3 id="sourceswitchingiterator-deadlock">SourceSwitchingIterator Deadlock</h3>
+<p>An instance of SourceSwitchingIterator, the Accumulo iterator which transparently
+manages whether data for a Tablet is in memory (the in-memory map) or disk (HDFS 
+after a minor compaction), was found deadlocked in a production system.</p>
+<p>This deadlock prevented the scan and the minor compaction from ever successfully
+completing without restarting the TabletServer. <a href="https://issues.apache.org/jira/browse/ACCUMULO-3745">ACCUMULO-3745</a>
+fixes the inconsistent synchronization inside of the SourceSwitchingIterator
+to prevent this deadlock from happening in the future.</p>
+<h3 id="table-flush-blocked-indefinitely">Table flush blocked indefinitely</h3>
+<p>While running the Accumulo Randomwalk distributed test, it was observed
+that all activity in Accumulo had stopped and there was an offline
+Accumulo metadata table tablet. The system first tried to flush a user
+tablet but the metadata table was not online (likely due to the agitation
+process which stops and starts Accumulo processes during the test). After
+this call, a call to load the metadata tablet was queued but could not 
+complete until the previous flush call. Thus, a deadlock occurred.</p>
+<p>This deadlock happened because the synchronous flush call could not complete
+before the load tablet call completed, but the load tablet call couldn't
+run because of connection caching we perform in Accumulo's RPC layer
+to reduce the quantity of sockets we need to create to send data. 
+<a href="https://issues.apache.org/jira/browse/ACCUMULO-3597">ACCUMULO-3597</a>
prevents this dealock by forcing a
+non-cached connection for the message requesting loads of metadata tablets,
+we can ensure that this deadlock won't occur.</p>
 <h2 id="performance-improvements">Performance Improvements</h2>
 <h3 id="performance-improvement-1">Performance Improvement 1</h3>
 <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt
ut labore et dolore magna aliqua.



Mime
View raw message