Author: billie
Date: Fri Mar 23 20:23:46 2012
New Revision: 1304582
URL: http://svn.apache.org/viewvc?rev=1304582&view=rev
Log:
ACCUMULO-145 fixed examples links, updated manual
Modified:
incubator/accumulo/site/trunk/content/accumulo/1.4/examples/index.mdtext
incubator/accumulo/site/trunk/content/accumulo/1.4/user_manual/Accumulo_Design.mdtext
Modified:
incubator/accumulo/site/trunk/content/accumulo/1.4/examples/index.mdtext
URL:
http://svn.apache.org/viewvc/incubator/accumulo/site/trunk/content/accumulo/1.4/examples/index.mdtext?rev=1304582&r1=1304581&r2=1304582&view=diff
==============================================================================
--- incubator/accumulo/site/trunk/content/accumulo/1.4/examples/index.mdtext
(original)
+++ incubator/accumulo/site/trunk/content/accumulo/1.4/examples/index.mdtext
Fri Mar 23 20:23:46 2012
@@ -35,29 +35,29 @@ Commands intended to be run in bash are
Commands intended to be run in the Accumulo shell are prefixed by '>'.
[1]: /accumulo/1.4/user_manual/Accumulo_Shell.html#User_Administration
-[batch](examples/batch.html)
+[batch](batch.html)
-[bloom](examples/bloom.html)
+[bloom](bloom.html)
-[bulkIngest](examples/bulkIngest.html)
+[bulkIngest](bulkIngest.html)
-[combiner](examples/combiner.html)
+[combiner](combiner.html)
-[constraints](examples/constraints.html)
+[constraints](constraints.html)
-[dirlist](examples/dirlist.html)
+[dirlist](dirlist.html)
-[filedata](examples/filedata.html)
+[filedata](filedata.html)
-[filter](examples/filter.html)
+[filter](filter.html)
-[helloworld](examples/helloworld.html)
+[helloworld](helloworld.html)
-[isolation](examples/isolation.html)
+[isolation](isolation.html)
-[mapred](examples/mapred.html)
+[mapred](mapred.html)
-[shard](examples/shard.html)
+[shard](shard.html)
-[visibility](examples/visibility.html)
+[visibility](visibility.html)
Modified:
incubator/accumulo/site/trunk/content/accumulo/1.4/user_manual/Accumulo_Design.mdtext
URL:
http://svn.apache.org/viewvc/incubator/accumulo/site/trunk/content/accumulo/1.4/user_manual/Accumulo_Design.mdtext?rev=1304582&r1=1304581&r2=1304582&view=diff
==============================================================================
---
incubator/accumulo/site/trunk/content/accumulo/1.4/user_manual/Accumulo_Design.mdtext
(original)
+++
incubator/accumulo/site/trunk/content/accumulo/1.4/user_manual/Accumulo_Design.mdtext
Fri Mar 23 20:23:46 2012
@@ -50,7 +50,7 @@ An instance of Accumulo includes many Ta
### <a id=Tablet_Server></a> 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 store.
+The TabletServer manages some subset of all the tablets (partitions of
tables). This includes receiving writes from clients, persisting writes to a
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 that was previously on a
server that failed, reapplying any writes found in the write-ahead log to the
tablet.
@@ -78,13 +78,13 @@ Accumulo stores data in tables, which ar
## <a id=Tablet_Service></a> Tablet Service
-When a write arrives at a TabletServer it is written to a WriteâAhead 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.
+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.
-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.
+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.
## <a id=Compactions></a> 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 keyâvalue pairs by omitting
keyâvalue pairs suppressed by a delete entry when the new file is created.
+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.
## <a id=Fault-Tolerance></a> Fault-Tolerance
