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Posted to commits@accumulo.apache.org by ct...@apache.org on 2015/04/08 20:04:15 UTC
accumulo git commit: ACCUMULO-2886 Update docs referring to ISAM files
Repository: accumulo
Updated Branches:
refs/heads/master 8b03718a7 -> 07507189f
ACCUMULO-2886 Update docs referring to ISAM files
* Replace references to ISAM files with references to RFiles
* Include brief explanation that RFile is a kind of ISAM
* Bump exec-maven-plugin version to get rid of warning during doc generation
Project: http://git-wip-us.apache.org/repos/asf/accumulo/repo
Commit: http://git-wip-us.apache.org/repos/asf/accumulo/commit/07507189
Tree: http://git-wip-us.apache.org/repos/asf/accumulo/tree/07507189
Diff: http://git-wip-us.apache.org/repos/asf/accumulo/diff/07507189
Branch: refs/heads/master
Commit: 07507189f8b9e0da1b50b9d08b4368bb8ca8b3dd
Parents: 8b03718
Author: Christopher Tubbs <ct...@apache.org>
Authored: Wed Apr 8 14:02:08 2015 -0400
Committer: Christopher Tubbs <ct...@apache.org>
Committed: Wed Apr 8 14:02:08 2015 -0400
----------------------------------------------------------------------
docs/src/main/asciidoc/chapters/design.txt | 25 +++++++++++++------------
pom.xml | 2 +-
2 files changed, 14 insertions(+), 13 deletions(-)
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http://git-wip-us.apache.org/repos/asf/accumulo/blob/07507189/docs/src/main/asciidoc/chapters/design.txt
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diff --git a/docs/src/main/asciidoc/chapters/design.txt b/docs/src/main/asciidoc/chapters/design.txt
index f975029..34cd459 100644
--- a/docs/src/main/asciidoc/chapters/design.txt
+++ b/docs/src/main/asciidoc/chapters/design.txt
@@ -124,25 +124,26 @@ image::data_distribution.png[width=500]
When a write arrives at a TabletServer it is written to a Write-Ahead Log and
then inserted into a sorted data structure in memory called a MemTable. When the
-MemTable reaches a certain size the TabletServer writes out the sorted key-value
-pairs to a file in HDFS called Indexed Sequential Access Method (ISAM)
-file. This process is called a minor compaction. A new MemTable is then created
-and the fact of the compaction is recorded in the Write-Ahead Log.
+MemTable reaches a certain size, the TabletServer writes out the sorted
+key-value pairs to a file in HDFS called a Relative Key File (RFile), which is a
+kind of Indexed Sequential Access Method (ISAM) file. This process is called a
+minor compaction. A new MemTable is then created and the fact of the compaction
+is recorded in the Write-Ahead Log.
When a request to read data arrives at a TabletServer, the TabletServer does a
binary search across the MemTable as well as the in-memory indexes associated
-with each ISAM file to find the relevant values. If clients are performing a
-scan, several key-value pairs are returned to the client in order from the
-MemTable and the set of ISAM files by performing a merge-sort as they are read.
+with each RFile to find the relevant values. If clients are performing a scan,
+several key-value pairs are returned to the client in order from the MemTable
+and the set of RFiles by performing a merge-sort as they are read.
=== Compactions
In order to manage the number of files per tablet, periodically the TabletServer
-performs Major Compactions of files within a tablet, in which some set of ISAM
-files are combined into one file. The previous files will eventually be removed
-by the Garbage Collector. This also provides an opportunity to permanently
-remove deleted key-value pairs by omitting key-value pairs suppressed by a
-delete entry when the new file is created.
+performs Major Compactions of files within a tablet, in which some set of RFiles
+are combined into one file. The previous files will eventually be removed by the
+Garbage Collector. This also provides an opportunity to permanently remove
+deleted key-value pairs by omitting key-value pairs suppressed by a delete entry
+when the new file is created.
=== Splitting
http://git-wip-us.apache.org/repos/asf/accumulo/blob/07507189/pom.xml
----------------------------------------------------------------------
diff --git a/pom.xml b/pom.xml
index 7ac9962..70ca34b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -708,7 +708,7 @@
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
- <version>1.3.2</version>
+ <version>1.4.0</version>
</plugin>
<plugin>
<groupId>org.eclipse.m2e</groupId>