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From mjw...@apache.org
Subject accumulo git commit: Updates for 1.8.0 release notes
Date Tue, 06 Sep 2016 20:57:11 GMT
Repository: accumulo
Updated Branches:
  refs/heads/gh-pages 535d261ed -> e5d6cc243


Updates for 1.8.0 release notes


Project: http://git-wip-us.apache.org/repos/asf/accumulo/repo
Commit: http://git-wip-us.apache.org/repos/asf/accumulo/commit/e5d6cc24
Tree: http://git-wip-us.apache.org/repos/asf/accumulo/tree/e5d6cc24
Diff: http://git-wip-us.apache.org/repos/asf/accumulo/diff/e5d6cc24

Branch: refs/heads/gh-pages
Commit: e5d6cc24322a8b119147d2dedf40585584cd6b94
Parents: 535d261
Author: Michael Wall <mjwall@gmail.com>
Authored: Tue Sep 6 16:57:05 2016 -0400
Committer: Michael Wall <mjwall@gmail.com>
Committed: Tue Sep 6 16:57:05 2016 -0400

----------------------------------------------------------------------
 release_notes/1.8.0.md | 33 +++++++++++++++++++++------------
 1 file changed, 21 insertions(+), 12 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/accumulo/blob/e5d6cc24/release_notes/1.8.0.md
----------------------------------------------------------------------
diff --git a/release_notes/1.8.0.md b/release_notes/1.8.0.md
index 979bfa0..de21e13 100644
--- a/release_notes/1.8.0.md
+++ b/release_notes/1.8.0.md
@@ -22,23 +22,28 @@ very seriously and have invested much time to ensure that we meet the
promises s
 
 ### Speed up WAL roll overs
 
-By creating active and standby Write-Ahead Log (WAL) files, switching to a new WAL is simplified
to an atomic
-reference switch of the WAL writer objects. This was a substantial refactor
-in they way WALs worked, but smoothes overal ingest performance in addition to provides a
increase in write speed
-as shown by the simple test below. The top entry is before [ACCUMULO-3423][ACCUMULO-3423]
and the bottom graph is after the refactor.
+Performance of writing mutations is improved by refactoring the
+bookeeping required for Write-Ahead Log (WAL) files and by creating a
+standby WAL for faster switching when the log is full. This was a
+substantial refactor in the way WALs worked, but smoothes overall
+ingest performance in addition to provides a increase in write speed
+as shown by the simple test below. The top entry is before
+[ACCUMULO-3423][ACCUMULO-3423] and the bottom graph is after the
+refactor.
 
 ![Graph of WAL speed up after ACCUMULO-3423][IMG-3423]
 
 ### User level API for RFile
 
 Previously the only public API available to write RFiles was via the AccumuloFileOutputFormat.
There was no way to read RFiles in the public
-API. [ACCUMULO-4165][ACCUMULO-4165] exposes a brand new public API for reading and writing
RFiles as well as cleans up some of the internal APIs.
+API. [ACCUMULO-4165][ACCUMULO-4165] exposes a brand new public [API][RFILE_API] for reading
and writing RFiles as well as cleans up some of the internal APIs.
 
 ### Suspend Tablet assignment for rolling restarts
 
 When a tablet server dies, Accumulo attempted to reassign the tablets as quickly as possible
to maintain availability.
 A new configuration property `table.suspend.duration` (with a default of zero seconds) now
controls how long to wait before reassigning
-a tablet from a dead tserver. The property is configurable in Zookeeper, so you can set it,
do a rolling restart, and then
+a tablet from a dead tserver. The property is configurable via the
+Accumulo shell, so you can set it, do a rolling restart, and then
 set it back to 0. A new state as introduced, TableState.SUSPENDED to support this feature.
By default, metadata tablet
 reassignment is not suspended, but that can also be changed with the `master.metadata.suspendable`
property that is false by
 default. Root tablet assignment can not be suspended. See [ACCUMULO-4353] for more info.
@@ -58,12 +63,15 @@ names do not change if this feature is not used.
 
 ### Rate limiting Major Compactions
 
-Major Compactions can significantly increase the amount of load on TabletServers. [ACCUMULO-4187]
takes a cue from Apache
-Cassandra and restricts the rate at which data is read and written when performing major
compactions. This has a direct effect
-on the IO load caused by major compactions with a similar effect on the CPU utilization.
This behavior is controlled
-by a new property `tserver.compaction.major.throughput` with a defaults of 0B which disables
the rate limiting.
+Major Compactions can significantly increase the amount of load on
+TabletServers. [ACCUMULO-4187] restricts the rate at which data is
+read and written when performing major compactions. This has a direct
+effect on the IO load caused by major compactions with a similar
+effect on the CPU utilization. This behavior is controlled by a new
+property `tserver.compaction.major.throughput` with a defaults of 0B
+which disables the rate limiting.
 
-### Sampling
+### Table Sampling
 
 Queryable sample data was added by [ACCUMULO-3913].  This allows users to configure a pluggable
 function to generate sample data.  At scan time, the sample data can optionally be scanned.
@@ -169,5 +177,6 @@ HDFS High-Availability instances, forcing NameNode failover.
 [THRIFT-0.9.3-RN]: https://github.com/apache/thrift/blob/0.9.3/CHANGES
 [api]: https://github.com/apache/accumulo/blob/1.8/README.md#api
 [semver]: http://semver.org
-[sample]: http://accumulo.apache.org/1.8/examples/sample
+[sample]: ../1.8/examples/sample
 [ITER_TEST]: https://accumulo.apache.org/1.8/accumulo_user_manual.html#_iterator_testing
+[RFILE_API]: ../1.8/apidocs/org/apache/accumulo/core/client/rfile/RFileWriter.html


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