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Posted to commits@accumulo.apache.org by bi...@apache.org on 2012/03/23 16:32:59 UTC
svn commit: r1304443 -
/incubator/accumulo/branches/1.4/docs/src/user_manual/chapters/design.tex
Author: billie
Date: Fri Mar 23 15:32:59 2012
New Revision: 1304443
URL: http://svn.apache.org/viewvc?rev=1304443&view=rev
Log:
ACCUMULO-491 changed hyphens
Modified:
incubator/accumulo/branches/1.4/docs/src/user_manual/chapters/design.tex
Modified: incubator/accumulo/branches/1.4/docs/src/user_manual/chapters/design.tex
URL: http://svn.apache.org/viewvc/incubator/accumulo/branches/1.4/docs/src/user_manual/chapters/design.tex?rev=1304443&r1=1304442&r2=1304443&view=diff
==============================================================================
--- incubator/accumulo/branches/1.4/docs/src/user_manual/chapters/design.tex (original)
+++ incubator/accumulo/branches/1.4/docs/src/user_manual/chapters/design.tex Fri Mar 23 15:32:59 2012
@@ -52,10 +52,10 @@ servers, one Garbage Collector process,
\subsection{Tablet Server}
The TabletServer manages some subset of all the tablets (partitions of tables). This includes receiving writes from clients, persisting writes to a
-writeâahead log, sorting new keyâvalue pairs in memory, periodically
-flushing sorted keyâvalue pairs to new files in HDFS, and responding
-to reads from clients, forming a mergeâsorted view of all keys and
-values from all the files it has created and the sorted inâmemory
+write-ahead log, sorting new key-value pairs in memory, periodically
+flushing sorted key-value pairs to new files in HDFS, and responding
+to reads from clients, forming a merge-sorted view of all keys and
+values from all the files it has created and the sorted in-memory
store.
TabletServers also perform recovery of a tablet
@@ -107,18 +107,18 @@ ingest and query load is balanced across
\section{Tablet Service}
-When a write arrives at a TabletServer it is written to a WriteâAhead Log and
+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 WriteâAhead Log.
+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 keyâvalue pairs are returned to the client in order from the
-MemTable and the set of ISAM files by performing a mergeâsort as they are read.
+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.
\section{Compactions}
@@ -126,7 +126,7 @@ In order to manage the number of files p
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 keyâvalue pairs by omitting keyâvalue pairs suppressed by a
+remove deleted key-value pairs by omitting key-value pairs suppressed by a
delete entry when the new file is created.
\section{Fault-Tolerance}