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Posted to commits@jena.apache.org by bu...@apache.org on 2014/11/16 15:35:17 UTC
svn commit: r929411 - in /websites/staging/jena/trunk/content: ./
documentation/tdb/store-parameters.html
Author: buildbot
Date: Sun Nov 16 14:35:17 2014
New Revision: 929411
Log:
Staging update by buildbot for jena
Modified:
websites/staging/jena/trunk/content/ (props changed)
websites/staging/jena/trunk/content/documentation/tdb/store-parameters.html
Propchange: websites/staging/jena/trunk/content/
------------------------------------------------------------------------------
--- cms:source-revision (original)
+++ cms:source-revision Sun Nov 16 14:35:17 2014
@@ -1 +1 @@
-1639990
+1639993
Modified: websites/staging/jena/trunk/content/documentation/tdb/store-parameters.html
==============================================================================
--- websites/staging/jena/trunk/content/documentation/tdb/store-parameters.html (original)
+++ websites/staging/jena/trunk/content/documentation/tdb/store-parameters.html Sun Nov 16 14:35:17 2014
@@ -147,13 +147,13 @@
<div id="breadcrumbs"></div>
<h1 class="title">TDB - Store Parameters</h1>
<p>TDB (as of version Jena 2.12.2, TDB 1.1.2) supports configuration of the
-databases when they are first created and each time an applciation connects
+databases when they are first created and each time an application connects
to an existing database. Databases using the default settings built-into
TDB continue to work exactly as before.</p>
<h2 id="per-connect-options">Per-connect Options</h2>
<p>The per-connect options are the ones that can be changed after the database has
been created and can be different each time the application attaches to the
-database. A database can have at most one JVM atatched to it (see Fuseki
+database. A database can have at most one JVM attached to it (see Fuseki
to share a database).</p>
<p>These options do not affect the on-disk structures.</p>
<table>
@@ -200,15 +200,21 @@ to share a database).</p>
<h3 id="file-access-mapped-and-direct-modes">File access - "mapped" and "direct" modes</h3>
<p>TDB has two modes of operation for accessing block files - "mapped" and
"direct".</p>
+<ul>
+<li>
<p>"mapped" uses memory mapped files and so the operating system is managing
-caching, flexing the amountof memory for file system cache to balance
+caching, flexing the amount of memory for file system cache to balance
demands from other programmes on the same hardware.</p>
+</li>
+<li>
<p>"direct" using TDB's own in-heap block caching. It avoids the problem that
-adddfressing is limited to a total of about 1.5Gbytes o 32 bit java.</p>
-<p>By default, TDB uses memory mapped files on 64 bit java and it's own file
+addressing is limited to a total of about 1.5Gbytes on 32 bit Java.</p>
+</li>
+</ul>
+<p>By default, TDB uses memory mapped files on 64 bit Java and it's own file
caching on 32 bit java.</p>
-<p>"mapped" databases can bnot be deleted while the JVM is running on MS
-Windows. This is a known issue with java.</p>
+<p>On Microsoft Windows, "mapped" databases can not be deleted while the JVM is running on MS
+Windows. This is a <a href="http://bugs.java.com/view_bug.do?bug_id=4715154">known issue with Java</a>.</p>
<p>TDB databases are compatible across these file modes. There is no
difference to the file layouts. Memory mapped files may appear larger
because they contain unused space. Some utilities report this in file
@@ -222,7 +228,7 @@ cache sizes are tuned to 32 bit Java.</p
beneficial.</p>
<h2 id="static-options">Static Options</h2>
<p>While it is possible to customize a database, this is considered to be
-experimental. It is possible to corrupt, unrecoverably, existing databases
+experimental. It is possible to corrupt, unrecoverable, existing databases
and create nonsense databases with inappropriate settings. It will be
useful in very few real situations. Not all combinations of index choices
will work. Only the standard layout is supported; alternative schemes are
@@ -230,13 +236,13 @@ for experimentation only.</p>
<h3 id="block-size">Block Size</h3>
<p>The block size can not be changed once a database has been created.</p>
<p>While the code attempts to detect block size mismatches, in order to retain
-compatibility with existing database, the testiong can not be perfect. If
+compatibility with existing database, the testing can not be perfect. If
undetected, any update will permanently and irrecoverably damage the
-datbase.</p>
+database.</p>
<h2 id="store-parameters-file-format">Store Parameters File Format</h2>
<p>JSON is used for the on-disk record of store parameters, see the example
-below. Unspecified options defaults to the for the runnign setup.</p>
-<p>These are default settings for a 64 bit java:</p>
+below. Unspecified options defaults to the for the running setup.</p>
+<p>These are default settings for a 64 bit Java:</p>
<p><code>{
"tdb.file_mode" : "mapped" ,
"tdb.block_size" : 8192 ,
@@ -260,16 +266,16 @@ below. Unspecified options defaults to
<h2 id="choosing-the-store-parameters">Choosing the store parameters</h2>
<p>This is the policy applied when creating or reattaching to a database.</p>
<p>If the database location has a parameter file, <code>tdb.cfg</code> then use that.
-This is modified by any dynamic options supplyed by the application. So to
-create a speciaalize database, one way to do that is to create an empty
+This is modified by any dynamic options supplied by the application. So to
+create a specialized database, one way to do that is to create an empty
directory and put a <code>tdb.cfg</code> in place.</p>
<p>If there is no parameter file and this this is a new database, use the
application provided store parameters, or if there are no application
provided parameters, use the system default parameters. If application
-supplied parameters are used, write a <code>tdg.cfg</code> file.</p>
-<p>Finally, if this is an existing database, with no <code>tdg.cfg</code>, use the system
+supplied parameters are used, write a <code>tdb.cfg</code> file.</p>
+<p>Finally, if this is an existing database, with no <code>tdb.cfg</code>, use the system
default modified by any application parameters.</p>
-<p>In other words, if there is no <code>tdg.cfg</code> assume the system defaults, except
+<p>In other words, if there is no <code>tdb.cfg</code> assume the system defaults, except
when creating a database.</p>
<p><em>Modification</em> involves taking one set of store parameters and applying any
dynamic parameters set in the second set. Only explicitly set dynamic