/usr/share/doc/polyorb-doc/html/polyorb_ug/PolyORB-ORB-Tasking-policies.html

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- This is free software; you can redistribute it and/or modify it under
terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.  This software is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>. -->
<!-- Created by GNU Texinfo 6.3, http://www.gnu.org/software/texinfo/ -->
<head>
<title>PolyORB User&rsquo;s Guide: PolyORB ORB Tasking policies</title>

<meta name="description" content="PolyORB User&rsquo;s Guide: PolyORB ORB Tasking policies">
<meta name="keywords" content="PolyORB User&rsquo;s Guide: PolyORB ORB Tasking policies">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<link href="About-This-Guide.html#About-This-Guide" rel="start" title="About This Guide">
<link href="Index.html#Index" rel="index" title="Index">
<link href="About-This-Guide.html#SEC_Contents" rel="contents" title="Table of Contents">
<link href="Tasking-model-in-PolyORB.html#Tasking-model-in-PolyORB" rel="up" title="Tasking model in PolyORB">
<link href="PolyORB-Tasking-configuration.html#PolyORB-Tasking-configuration" rel="next" title="PolyORB Tasking configuration">
<link href="PolyORB-Tasking-runtimes.html#PolyORB-Tasking-runtimes" rel="prev" title="PolyORB Tasking runtimes">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
blockquote.smallquotation {font-size: smaller}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
div.lisp {margin-left: 3.2em}
div.smalldisplay {margin-left: 3.2em}
div.smallexample {margin-left: 3.2em}
div.smalllisp {margin-left: 3.2em}
kbd {font-style: oblique}
pre.display {font-family: inherit}
pre.format {font-family: inherit}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
pre.smalldisplay {font-family: inherit; font-size: smaller}
pre.smallexample {font-size: smaller}
pre.smallformat {font-family: inherit; font-size: smaller}
pre.smalllisp {font-size: smaller}
span.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
ul.no-bullet {list-style: none}
-->
</style>


</head>

<body lang="en">
<a name="PolyORB-ORB-Tasking-policies"></a>
<div class="header">
<p>
Next: <a href="PolyORB-Tasking-configuration.html#PolyORB-Tasking-configuration" accesskey="n" rel="next">PolyORB Tasking configuration</a>, Previous: <a href="PolyORB-Tasking-runtimes.html#PolyORB-Tasking-runtimes" accesskey="p" rel="prev">PolyORB Tasking runtimes</a>, Up: <a href="Tasking-model-in-PolyORB.html#Tasking-model-in-PolyORB" accesskey="u" rel="up">Tasking model in PolyORB</a> &nbsp; [<a href="About-This-Guide.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index.html#Index" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<a name="PolyORB-ORB-Tasking-policies-1"></a>
<h3 class="section">5.2 PolyORB ORB Tasking policies</h3>

<p>PolyORB ORB Tasking policies control the creation of tasks to
process all middleware internal jobs, e.g. request processing, I/O
monitoring.
</p>
<p><i>Note: there is a dependency between ORB Tasking policies, and the
runtime used, as detailed below.</i>
</p>
<a name="No-Tasking"></a>
<h4 class="subsection">5.2.1 No Tasking</h4>

<p>Under the No Tasking ORB policy, no tasks are created within the
middleware instance: it uses the environment task to process all
jobs. Note that this policy is not thread safe and is compatible with
the No tasking runtime only.
</p>
<a name="Thread-Pool"></a>
<h4 class="subsection">5.2.2 Thread Pool</h4>

<p>Under the Thread Pool ORB policy, the middleware creates a pool of
threads during initialization of PolyORB. This pool processes all
jobs. The number of tasks in the thread pool can be configured by three
parameters in the <code>[tasking]</code> configuration section.
</p>
<ul>
<li> <code>min_spare_threads</code> indicates the number of tasks
created at startup.

</li><li> <code>max_spare_threads</code> is a ceiling. When a remote subprogram
call is completed, its anonymous task is deallocated if the number of
unused tasks already in the pool is greater than the ceiling. If not,
then the task is queued in the pool.

</li><li> <code>max_threads</code> indicates the maximum number of tasks in the pool.

</li></ul>

<p>See <a href="PolyORB-Tasking-configuration.html#PolyORB-Tasking-configuration">PolyORB Tasking configuration</a>, for more information on how to
configure the number of tasks in the thread pool.
</p>
<a name="Thread-Per-Session"></a>
<h4 class="subsection">5.2.3 Thread Per Session</h4>

<p>Under the Thread Per Session ORB policy, the middleware creates one
task when a new session (one active connection) is opened. The task
terminates when the session is closed.
</p>
<a name="Thread-Per-Request"></a>
<h4 class="subsection">5.2.4 Thread Per Request</h4>

<p>Under the Thread Per Request ORB policy, the middleware creates one
task per incoming request. The task terminates when the request is
completed.
</p>
<hr>
<div class="header">
<p>
Next: <a href="PolyORB-Tasking-configuration.html#PolyORB-Tasking-configuration" accesskey="n" rel="next">PolyORB Tasking configuration</a>, Previous: <a href="PolyORB-Tasking-runtimes.html#PolyORB-Tasking-runtimes" accesskey="p" rel="prev">PolyORB Tasking runtimes</a>, Up: <a href="Tasking-model-in-PolyORB.html#Tasking-model-in-PolyORB" accesskey="u" rel="up">Tasking model in PolyORB</a> &nbsp; [<a href="About-This-Guide.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Index.html#Index" title="Index" rel="index">Index</a>]</p>
</div>



</body>
</html>
polyorb-doc 2.11~20140418-3.2 / usr / share / doc / polyorb-doc / html / polyorb_ug / PolyORB-ORB-Tasking-policies.html
