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From els...@apache.org
Subject svn commit: r1627089 - /accumulo/site/trunk/content/release_notes/1.5.2.mdtext
Date Tue, 23 Sep 2014 16:53:31 GMT
Author: elserj
Date: Tue Sep 23 16:53:31 2014
New Revision: 1627089

URL: http://svn.apache.org/r1627089
Log:
Some more minor changes

Modified:
    accumulo/site/trunk/content/release_notes/1.5.2.mdtext

Modified: accumulo/site/trunk/content/release_notes/1.5.2.mdtext
URL: http://svn.apache.org/viewvc/accumulo/site/trunk/content/release_notes/1.5.2.mdtext?rev=1627089&r1=1627088&r2=1627089&view=diff
==============================================================================
--- accumulo/site/trunk/content/release_notes/1.5.2.mdtext (original)
+++ accumulo/site/trunk/content/release_notes/1.5.2.mdtext Tue Sep 23 16:53:31 2014
@@ -64,10 +64,10 @@ HeapIterator in common cases.
 
 In Hadoop-2, two implementations of sync are provided: hflush and hsync. Both of these
 methods provide a way to request that the datanodes write the data to the underlying
-medium and not just hold it in memory (the 'fsync' syscall). While both of these methods
-inform the Datanodes to sync the relevant block(s), hflush does not wait for acknowledgement
-from the Datanodes that the sync finished, where hsync does. To provide the most reliable
system
-"out of the box", Accumulo defaults to hsync so that your data is as secure as possible in

+medium and not just hold it in memory (the *fsync* syscall). While both of these methods
+inform the Datanodes to sync the relevant block(s), *hflush* does not wait for acknowledgement
+from the Datanodes that the sync finished, where *hsync* does. To provide the most reliable
system
+"out of the box", Accumulo defaults to *hsync* so that your data is as secure as possible
in 
 a variety of situations (notably, unexpected power outages).
 
 The downside is that performance tends to suffer because waiting for a sync to disk is a
very
@@ -76,7 +76,7 @@ that lets users to change the HDFS sync 
 of *hsync* may result in about a 30% increase in ingest performance.
 
 For users upgrading from Hadoop-1 or Hadoop-0.20 releases, *hflush* is the equivalent of
how
-sync was implemented and should give equivalent performance.
+sync was implemented in these older versions of Hadoop and should give comparable performance.
 
 ### Server-side mutation queue size
 



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