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From ktur...@apache.org
Subject svn commit: r1230198 - /incubator/accumulo/branches/1.4/docs/isolation.html
Date Wed, 11 Jan 2012 19:18:38 GMT
Author: kturner
Date: Wed Jan 11 19:18:38 2012
New Revision: 1230198

URL: http://svn.apache.org/viewvc?rev=1230198&view=rev
Log:
ACCUMULO-285 use new example package in isolation doc

Modified:
    incubator/accumulo/branches/1.4/docs/isolation.html

Modified: incubator/accumulo/branches/1.4/docs/isolation.html
URL: http://svn.apache.org/viewvc/incubator/accumulo/branches/1.4/docs/isolation.html?rev=1230198&r1=1230197&r2=1230198&view=diff
==============================================================================
--- incubator/accumulo/branches/1.4/docs/isolation.html (original)
+++ incubator/accumulo/branches/1.4/docs/isolation.html Wed Jan 11 19:18:38 2012
@@ -31,7 +31,7 @@
  <li>iterators executed as part of a minor or major compaction 
  <li>bulk import of new files
 </ul>
-Isolation guarantees that either all or none of the changes made by these operations on a
row are seen.  Use the <a href='apidocs/org/apache/accumulo/core/client/IsolatedScanner.html'>IsolatedScanner</a>
to obtain an isolated view of an accumulo table.  When using the regular scanner it is possible
to see a non isolated view of a row.  For example if a mutation modifies three columns, it
is possible that you will only see two of those modifications.  With the isolated scanner
either all three of the changes are seen or none.  For an example of this try running the
<a href='apidocs/org/apache/accumulo/examples/isolation/InterferenceTest.html'>InterferenceTest</a>
example.  
+Isolation guarantees that either all or none of the changes made by these operations on a
row are seen.  Use the <a href='apidocs/org/apache/accumulo/core/client/IsolatedScanner.html'>IsolatedScanner</a>
to obtain an isolated view of an accumulo table.  When using the regular scanner it is possible
to see a non isolated view of a row.  For example if a mutation modifies three columns, it
is possible that you will only see two of those modifications.  With the isolated scanner
either all three of the changes are seen or none.  For an example of this try running the
<a href='apidocs/org/apache/accumulo/examples/simple/isolation/InterferenceTest.html'>InterferenceTest</a>
example.  
 
 <p>At this time there is no client side isolation support for the <a href='apidocs/org/apache/accumulo/core/client/BatchScanner.html'>BatchScanner</a>.
 You may consider using the <a href='apidocs/org/apache/accumulo/core/iterators/WholeRowIterator.html'>WholeRowIterator</a>
with the  <a href='apidocs/org/apache/accumulo/core/client/BatchScanner.html'>BatchScanner</a>
to achieve isolation though. This drawback of doing this is that entire rows are read into
memory on the server side.  If a row is too big, it may crash a tablet server.  The <a
href='apidocs/org/apache/accumulo/core/client/IsolatedScanner.html'>IsolatedScanner</a>
buffers rows on the client side so a large row will not crash a tablet server.
 



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