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 <h1>Parallel Debugging</h1>
 <p>This section describes the features of PTP that enable a developer to debug a parallel application. The topics that will be covered include:</p>
 <ul>
 <li><a href="#launch">Creating a Debug Launch Configuration</a></li>
 <li><a href="#feat">The Parallel Debug Perspective </a></li>
 <li><a href="#pSets">Process Sets</a></li>
 <li><a href="#pSetsOper">Operations on Process Sets</a></li>
 <li><a href="#pSetsCreate">Managing Process Sets</a></li>
 <li><a href="#bkpt">Breakpoints</a></li>
 <li><a href="#cip">Current Instruction Pointer</a></li>
 <li><a href="#reg">Process Registration </a> and the Debug view (including stack traces)</li>
 <li><a href="#finish">Terminating Execution</a></li>
 </ul>

 <h2 id="launch">Creating a Debug Launch Configuration</h2>
 In order to launch a debug job, the user must first create a Debug Configuration. The process for doing this is identical to that used to
 <a href="03pLaunchConfig.html">run a parallel program</a>,
 with the exception of a single extra tab that needs to be completed. Only this extra tab will be described here.
 <p>
 To create a debug configuration, use the following steps:
 <ol>
 <li>Select the <b>Run &gt; Debug Configurations...</b> menu.
 <p><br></p>
 </li>
 <li>Follow the same steps as described in <a href="03pLaunchConfig.html">running parallel programs</a> for completing the other launch tabs, e.g.
 Resources, Application, Arguments, Environment, Synchronize.
 <p><br></p>
 </li>
 <li>Switch to the <b>Debugger</b> tab.
 <p><br></p>
 <p><img src="images/06launchConfig.png"></p>
 <p><br></p>
 </li>
 <li>If no debugger is visible in the <b>Debugger</b> drop-down,
 	select one. This is the debugger that will control the parallel debug
 	session. Currently only <b>SDM</b> is supported (SDM stands for
 	Scalable Debug Manager), so select this.
 	<p><br></p>
 	</li>
 	<li>
 	If you wish the debugger to automatically suspend the
 	application on launch, make sure <b>Stop at main() on startup</b> is
 	checked
 	<p><br></p>
 	</li>
 	<li>
 	Under <b>Debugger Options</b>, leave the <b>Debugger backend</b> set to <code>gdb-mi</code>.
 	<p><br></p>
 	</li>
 	<li>Make sure that the <b>Path to debugger
 	executable</b> is correct.
 	<p><br></p>
 	<p>If you are debugging on the local machine, this path should
 	point to the <code>sdm</code> executable in your Ecilpse installation's
 	<code>plugins/org.eclipse.ptp.<i>os.arch_version</i>/bin</code>
 	directory, where <code><i>os.arch_version</i></code> is your operating
 	system (<code>linux</code>, <code>macosx</code>, or <code>aix</code>),
 	architecture (<code>x86</code>, <code>x86_64</code>, or <code>ppc</code>),
 	and version number of the plugin (e.g. <code>5.0.0.201106080812</code>).</p>
 	<p><br></p>
 	<b>Note: This may have required an extra step during installation to build this executable.</b>
 	<p><br></p>
 	<p>If you are debugging remotely, then this path will be the path
 	to where the <code>sdm</code> executable was installed on the remote
 	machine.</p>
 	<p><br></p>
 	</li>
 	<li>
 	<p>Set the <b>Debugger session address</b>. This is the address
 	that the debugger will connect to when it starts, and will depend on
 	where you are launching the application:</p>
 	<p><br></p>
 	<p>If you are launching onto the local machine, or onto a remote
 	machine using port forwarding, use <code>localhost</code>. (Note that
 	you will need to have the <code>GatewayPorts</code> option set to <code>yes</code>
 	in the <code>sshd</code> configuration file on the remote system for
 	this to work with port forwarding.)</p>
 	<p><br></p>
 	<p>If you are launching onto a remote machine without using port
 	forwarding, then this should be the address of the local machine (the
 	one running Eclipse). <i>This address must be accessible from the
 	remote machine.</i>. If your local network configuration precludes the
 	remote machine accessing your local machine, you will need to
 	reconfigure the resource manager to use port forwarding.</p>
 	</li>
 	</ol>


 <h2 id="feat">The Parallel Debug perspective</h2>
 <p>The Parallel Debug perspective is used when debugging a parallel application. The default behavior is to switch to the
 perspective when a debug session is launched. Experienced Eclipse users will notice that many
 of the views are similar to those available in the CDT Debug perspective. Please refer to the <b>C/C++ Development User Guide</b> for
 a description of these views.</p>

 <p><img src="images/06ptpDebugPersp.png"></p>
 <p>This image shows a typical debug session. In the upper left of the perspective is the <b>Parallel Debug view</b> which shows the processes associated with the job,
 and allows bulk control of the processes. Underneath this is the <b>Debug view</b> which is the standard view showing process threads and stack frames. The
 source window shows a current line marker, which represents the current location of all 64 processes. In the upper right, the Variables view
  is showing the variables from the processes currently selected in the Debug view. There are also a number of other views available for setting breakpoints,
  manipulating signals, etc. Below this is the standard <b>Outline view</b>. At the very bottom are the standard <b>Problems</b>, <b>Console</b>, and <b>Memory</b>
  views.</p>

 <h2 id="pSets">Process Sets</h2>
 <p>A key concept for debugging parallel programs with PTP is the notion of a <i>process set</i>. Traditional debuggers apply operations to a single
 process.  Parallel debugging operations apply to arbitrary collections of processes (including a single process). The PTP debugger calls these arbitrary
 collections process sets, and uses them as a means of simultaneously referring to one or more processes.</p>

 <p>When a parallel debug session is first started, all processes are contained
 in a set, called the <b>Root</b> set.  Sets are always associated with a single Job.
 A job can have any number of process sets, and a set can contain from 1 to the
 number of processes in a job. Process sets from the same job can contain overlapping sets of processes. This is
 shown in the following diagram.</p>

 <p><img src="images/06pSets.png"></p>

 <p>Debug commands on the Parallel Debug view toolbar always apply to the <i>current process set</i>, which is the set of processes that is visible in the view.</p>

 <p><img src="images/06parallelDebugViewCmds.png"></p>

 <h2 id="pSetsOper">Operations on Process sets</h2>

 <p>PTP provides buttons on the toolbar of the Parallel Debug view
 to create, modify, and delete process sets, and to change
 the current process set.</p>

 <p><img src="images/06parallelDebugViewSets.png"></p>


 <h2 id="pSetsCreate">Managing Process Sets</h2>

 <p>Select the processes to be placed in the set
 by selecting a rectangular region with the mouse,
 or click the mouse and shift-click or ctrl-click to
 select a contiguous region, or separate processes, respectively.</p>

 <p>For example, to select a rectangular set of processes:</p>

 <p><img src="images/06pSetSelect.png")</script></p>

 <p>Once the processes have been selected, create a process set clicking on the <b>Create Set button</b> <img src="images/06createProcessSetIcon.png">.</p>

 <p><img src="images/06selectProcessSetCreate.png")</script></p>

 <p>To add processes to an existing process set, select the processes you wish to add and click on
 the down-arrow <img src="images/06downArrowSelect.png"> to the right of the icon:</p>

 <p><img src="images/06selectProcessSetCreateAdd.png"></p>


 <p>To change the current process set, select the <b>Change Set button</b>
 <img src="images/06pSetChooseIcon.png">
 and choose from the list via the down-arrow <img src="images/06downArrowSelect.png">, or
 click on the button itself to cycle through the sets.</p>

 <p><img src="images/06pSetChange.png")</script></p>

 <p>To remove processes from the <i>current set</i>, select the processes
 as described above, and click the
 <b>Remove Elements button</b>.</p>

 <p><img src="images/06pSetRemove.png"></p>

 <p>Select the <b>Delete Set button</b> to delete the current process set:</p>

 <p><img src="images/06pSetDelete.png"></p>

 <h2 id="bkpt">Breakpoints</h2>
 <p>PTP has a special type of breakpoint known as a <i>parallel breakpoint</i>. These breakpoints differ from normal breakpoints
 because they apply to a set of processes instead of a single process (or thread). There are two types of parallel breakpoints:</p>

 <ul>
 <li><p><i>Global breakpoints</i> apply to <i>all</i> processes in <i>any</i> job. A global breakpoint remains in effect between job launches.
 Typically, a global breakpoint is used for gaining control of an application at a predetermined point. Global breakpoints are identified by a
 parallel breakpoint icon with a small <code>G</code> in the upper left corner:</p>
 <p><br></p>
 <p><img src="images/06globalBreakpoint.png"></p>
 <p><br></p>
 </li>

 <li><p><i>Set Breakpoints </i> apply only to a <i>specific set</i> of processes
 (which can include the root set) for a <i>single</i> job. When the job completes,
 these breakpoints are removed.</p>
 <p><br></p>
 <p><img src="images/06setBreakpoint.png"></p>
 <p><br></p>
 </li>
 <p>Set breakpoints can be one of three colors:<p>
 <ul>
 <li><p>Green indicates the breakpoint applies to the current set.</p></li>
 <li><p>Blue indicates the breakpoint applies to some other set than the current set, but there are overlapping processes in the sets.</p></li>
 <li><p>Yellow indicates the breakpoint applies to some other set than the current set, and there are no overlapping processes in the sets.</p></li>
 </ul>
 </ul>

 <h3>Setting a breakpoint</h3><p>
 To create a breakpoint, double-click on the left edge of
 an editor window, at the line on which you want to set the breakpoint.
 You can also right-click and use the <b>Parallel Breakpoint &gt; Toggle breakpoint</b> context menu.</p>

 <p><img src="images/06bkptSetContext.png"></p>

 <p>A global breakpoint is created if no jobs are selected in the Parallel Debug view.
 If a job is selected, the breakpoint will apply to the current set.</p>

 <h3>Breakpoint information</h3>

 <p>There are a number of ways to find out more information about a breakpoint, such as the source file, line and process set it applies to.
 Placing the mouse over a breakpoint will display a tooltip popup:</p>

 <p><img src="images/06bkptHover.png"></p>

 <p>The <b>Breakpoints view</b> can be used to see all breakpoints that have been created: </p>

 <p><img src="images/06bkptsView.png"></p>

 <p>Use <b>Show &gt; Parallel Breakpoint Set</b> in the menu on the Breakpoints view toolbar to group breakpoints
 by the process set they apply to:</p>

 <p><img src="images/06bkptsViewMenu.png"></p>

 <p>For example the above selection will list the breakpoints
 by process set:</p>

 <p><img src="images/06bkptsViewByProcessSet.png"></p>

 <h2 id="cip">Current Instruction Pointer</h2>
 <p>The current instruction pointer is used to show the current
 location of <i>suspended</i> processes.
 In traditional programs, there is only a single instruction pointer displayed at any one time.
 In parallel programs, there is an instruction pointer for every process.</p>

 <p>The PTP debugger shows one instruction pointer for
 <i>every group of processes at the same location</i>. In the following example, there are processes suspended
 at three different locations in the program.</p>

 <p><img src="images/06mip.png"></p>

 <p><i>The group of processes represented by an instruction pointer
 is not necessarily the same as a process set.</i></p>

 <p>Different markers are used to indicate the types of processes stopped at that location (the different types will be discussed below):</p>
 <ul>
 <li><p><img src="images/06ipReg.png">Registered processes marker</p></li>
 <li><p><img src="images/06ipUnreg.png">Un-registered processes marker</p></li>
 <li><p><img src="images/06ipMult.png">Marker indicating a combination of registered and un-registered processes</p></li>
 </ul>

 <p>Placing the mouse over an instruction pointer provides additional information about the processes suspended at that location:</p>
 <p><img src="images/06cipHover.png"></p>

 <h2 id="reg">Process Registration and the Debug View</h2>

 <p>Once processes of a parallel job have been suspended, it is often desirable to obtain more detailed information about an individual process.
 In order to do this, a particular process must first be <i>registered</i>. Once a process is registered it's threads and stack frames appear in
 the Debug view. By selecting the stack frame in this view, detailed information about the local variables can be obtained in the Variables view.</p>

 <p>Any number of processes can be registered, and processes can be registered or un-registered at any time. To register a process, double-click its
 process icon in the Parallel Debug view. A black box will be shown around the process icon to indicate that it has been registered. At the same time,
 the process will appear in the Debug view.</p>

 <p><img src="images/06reg1.png"></p>

 <p>To un-register a process, double-click on the same process icon. The box disappears, and the process is removed from the debug view.</p>

 <p>The Debug view also provides a set of debug commands (resume, pause, step over, etc.) that apply to the <i>currently selected process</i> in the view.
 This provides a convenient means of controlling individual processes.</p>

 <h2 id="finish">Terminating Execution</h2>
 At the end of a debug session, it is necessary to terminate the execution of the job. To do this, click on the terminate icon
 <img src="images/06terminateAll.png"> in the Parallel Debug view.  Note that the terminate icon in the Debug view
  <img src="images/06terminate.png"> will only terminate the currently selected process in that view.

 <p><a href="#top">Back to Top</a> | <a href="toc.html">Back to Table of Contents</a>

 </body>
 </html>
	<html>
	<head>
	<title>Parallel Debugging</title>
	<link rel="stylesheet" type="text/css" href="help.css">
	<script type="text/javascript" src="thumb.js"> </script>
	</head>
	<body>
	<!-- test -->
	<h1>Parallel Debugging</h1>
	<p>This section describes the features of PTP that enable a developer to debug a parallel application. The topics that will be covered include:</p>
	<ul>
	<li><a href="#launch">Creating a Debug Launch Configuration</a></li>
	<li><a href="#feat">The Parallel Debug Perspective </a></li>
	<li><a href="#pSets">Process Sets</a></li>
	<li><a href="#pSetsOper">Operations on Process Sets</a></li>
	<li><a href="#pSetsCreate">Managing Process Sets</a></li>
	<li><a href="#bkpt">Breakpoints</a></li>
	<li><a href="#cip">Current Instruction Pointer</a></li>
	<li><a href="#reg">Process Registration </a> and the Debug view (including stack traces)</li>
	<li><a href="#finish">Terminating Execution</a></li>
	</ul>

	<h2 id="launch">Creating a Debug Launch Configuration</h2>
	In order to launch a debug job, the user must first create a Debug Configuration. The process for doing this is identical to that used to
	<a href="03pLaunchConfig.html">run a parallel program</a>,
	with the exception of a single extra tab that needs to be completed. Only this extra tab will be described here.
	<p>
	To create a debug configuration, use the following steps:
	<ol>
	<li>Select the <b>Run > Debug Configurations...</b> menu.
	<p><br></p>
	</li>
	<li>Follow the same steps as described in <a href="03pLaunchConfig.html">running parallel programs</a> for completing the other launch tabs, e.g.
	Resources, Application, Arguments, Environment, Synchronize.
	<p><br></p>
	</li>
	<li>Switch to the <b>Debugger</b> tab.
	<p><br></p>
	<p><img src="images/06launchConfig.png"></p>
	<p><br></p>
	</li>
	<li>If no debugger is visible in the <b>Debugger</b> drop-down,
	select one. This is the debugger that will control the parallel debug
	session. Currently only <b>SDM</b> is supported (SDM stands for
	Scalable Debug Manager), so select this.
	<p><br></p>
	</li>
	<li>
	If you wish the debugger to automatically suspend the
	application on launch, make sure <b>Stop at main() on startup</b> is
	checked
	<p><br></p>
	</li>
	<li>
	Under <b>Debugger Options</b>, leave the <b>Debugger backend</b> set to <code>gdb-mi</code>.
	<p><br></p>
	</li>
	<li>Make sure that the <b>Path to debugger
	executable</b> is correct.
	<p><br></p>
	<p>If you are debugging on the local machine, this path should
	point to the <code>sdm</code> executable in your Ecilpse installation's
	<code>plugins/org.eclipse.ptp.<i>os.arch_version</i>/bin</code>
	directory, where <code><i>os.arch_version</i></code> is your operating
	system (<code>linux</code>, <code>macosx</code>, or <code>aix</code>),
	architecture (<code>x86</code>, <code>x86_64</code>, or <code>ppc</code>),
	and version number of the plugin (e.g. <code>5.0.0.201106080812</code>).</p>
	<p><br></p>
	<b>Note: This may have required an extra step during installation to build this executable.</b>
	<p><br></p>
	<p>If you are debugging remotely, then this path will be the path
	to where the <code>sdm</code> executable was installed on the remote
	machine.</p>
	<p><br></p>
	</li>
	<li>
	<p>Set the <b>Debugger session address</b>. This is the address
	that the debugger will connect to when it starts, and will depend on
	where you are launching the application:</p>
	<p><br></p>
	<p>If you are launching onto the local machine, or onto a remote
	machine using port forwarding, use <code>localhost</code>. (Note that
	you will need to have the <code>GatewayPorts</code> option set to <code>yes</code>
	in the <code>sshd</code> configuration file on the remote system for
	this to work with port forwarding.)</p>
	<p><br></p>
	<p>If you are launching onto a remote machine without using port
	forwarding, then this should be the address of the local machine (the
	one running Eclipse). <i>This address must be accessible from the
	remote machine.</i>. If your local network configuration precludes the
	remote machine accessing your local machine, you will need to
	reconfigure the resource manager to use port forwarding.</p>
	</li>
	</ol>


	<h2 id="feat">The Parallel Debug perspective</h2>
	<p>The Parallel Debug perspective is used when debugging a parallel application. The default behavior is to switch to the
	perspective when a debug session is launched. Experienced Eclipse users will notice that many
	of the views are similar to those available in the CDT Debug perspective. Please refer to the <b>C/C++ Development User Guide</b> for
	a description of these views.</p>

	<p><img src="images/06ptpDebugPersp.png"></p>
	<p>This image shows a typical debug session. In the upper left of the perspective is the <b>Parallel Debug view</b> which shows the processes associated with the job,
	and allows bulk control of the processes. Underneath this is the <b>Debug view</b> which is the standard view showing process threads and stack frames. The
	source window shows a current line marker, which represents the current location of all 64 processes. In the upper right, the Variables view
	is showing the variables from the processes currently selected in the Debug view. There are also a number of other views available for setting breakpoints,
	manipulating signals, etc. Below this is the standard <b>Outline view</b>. At the very bottom are the standard <b>Problems</b>, <b>Console</b>, and <b>Memory</b>
	views.</p>

	<h2 id="pSets">Process Sets</h2>
	<p>A key concept for debugging parallel programs with PTP is the notion of a <i>process set</i>. Traditional debuggers apply operations to a single
	process. Parallel debugging operations apply to arbitrary collections of processes (including a single process). The PTP debugger calls these arbitrary
	collections process sets, and uses them as a means of simultaneously referring to one or more processes.</p>

	<p>When a parallel debug session is first started, all processes are contained
	in a set, called the <b>Root</b> set. Sets are always associated with a single Job.
	A job can have any number of process sets, and a set can contain from 1 to the
	number of processes in a job. Process sets from the same job can contain overlapping sets of processes. This is
	shown in the following diagram.</p>

	<p><img src="images/06pSets.png"></p>

	<p>Debug commands on the Parallel Debug view toolbar always apply to the <i>current process set</i>, which is the set of processes that is visible in the view.</p>

	<p><img src="images/06parallelDebugViewCmds.png"></p>

	<h2 id="pSetsOper">Operations on Process sets</h2>

	<p>PTP provides buttons on the toolbar of the Parallel Debug view
	to create, modify, and delete process sets, and to change
	the current process set.</p>

	<p><img src="images/06parallelDebugViewSets.png"></p>


	<h2 id="pSetsCreate">Managing Process Sets</h2>

	<p>Select the processes to be placed in the set
	by selecting a rectangular region with the mouse,
	or click the mouse and shift-click or ctrl-click to
	select a contiguous region, or separate processes, respectively.</p>

	<p>For example, to select a rectangular set of processes:</p>

	<p><img src="images/06pSetSelect.png")</script></p>

	<p>Once the processes have been selected, create a process set clicking on the <b>Create Set button</b> <img src="images/06createProcessSetIcon.png">.</p>

	<p><img src="images/06selectProcessSetCreate.png")</script></p>

	<p>To add processes to an existing process set, select the processes you wish to add and click on
	the down-arrow <img src="images/06downArrowSelect.png"> to the right of the icon:</p>

	<p><img src="images/06selectProcessSetCreateAdd.png"></p>


	<p>To change the current process set, select the <b>Change Set button</b>
	<img src="images/06pSetChooseIcon.png">
	and choose from the list via the down-arrow <img src="images/06downArrowSelect.png">, or
	click on the button itself to cycle through the sets.</p>

	<p><img src="images/06pSetChange.png")</script></p>

	<p>To remove processes from the <i>current set</i>, select the processes
	as described above, and click the
	<b>Remove Elements button</b>.</p>

	<p><img src="images/06pSetRemove.png"></p>

	<p>Select the <b>Delete Set button</b> to delete the current process set:</p>

	<p><img src="images/06pSetDelete.png"></p>

	<h2 id="bkpt">Breakpoints</h2>
	<p>PTP has a special type of breakpoint known as a <i>parallel breakpoint</i>. These breakpoints differ from normal breakpoints
	because they apply to a set of processes instead of a single process (or thread). There are two types of parallel breakpoints:</p>

	<ul>
	<li><p><i>Global breakpoints</i> apply to <i>all</i> processes in <i>any</i> job. A global breakpoint remains in effect between job launches.
	Typically, a global breakpoint is used for gaining control of an application at a predetermined point. Global breakpoints are identified by a
	parallel breakpoint icon with a small <code>G</code> in the upper left corner:</p>
	<p><br></p>
	<p><img src="images/06globalBreakpoint.png"></p>
	<p><br></p>
	</li>

	<li><p><i>Set Breakpoints </i> apply only to a <i>specific set</i> of processes
	(which can include the root set) for a <i>single</i> job. When the job completes,
	these breakpoints are removed.</p>
	<p><br></p>
	<p><img src="images/06setBreakpoint.png"></p>
	<p><br></p>
	</li>
	<p>Set breakpoints can be one of three colors:<p>
	<ul>
	<li><p>Green indicates the breakpoint applies to the current set.</p></li>
	<li><p>Blue indicates the breakpoint applies to some other set than the current set, but there are overlapping processes in the sets.</p></li>
	<li><p>Yellow indicates the breakpoint applies to some other set than the current set, and there are no overlapping processes in the sets.</p></li>
	</ul>
	</ul>

	<h3>Setting a breakpoint</h3><p>
	To create a breakpoint, double-click on the left edge of
	an editor window, at the line on which you want to set the breakpoint.
	You can also right-click and use the <b>Parallel Breakpoint > Toggle breakpoint</b> context menu.</p>

	<p><img src="images/06bkptSetContext.png"></p>

	<p>A global breakpoint is created if no jobs are selected in the Parallel Debug view.
	If a job is selected, the breakpoint will apply to the current set.</p>

	<h3>Breakpoint information</h3>

	<p>There are a number of ways to find out more information about a breakpoint, such as the source file, line and process set it applies to.
	Placing the mouse over a breakpoint will display a tooltip popup:</p>

	<p><img src="images/06bkptHover.png"></p>

	<p>The <b>Breakpoints view</b> can be used to see all breakpoints that have been created: </p>

	<p><img src="images/06bkptsView.png"></p>

	<p>Use <b>Show > Parallel Breakpoint Set</b> in the menu on the Breakpoints view toolbar to group breakpoints
	by the process set they apply to:</p>

	<p><img src="images/06bkptsViewMenu.png"></p>

	<p>For example the above selection will list the breakpoints
	by process set:</p>

	<p><img src="images/06bkptsViewByProcessSet.png"></p>

	<h2 id="cip">Current Instruction Pointer</h2>
	<p>The current instruction pointer is used to show the current
	location of <i>suspended</i> processes.
	In traditional programs, there is only a single instruction pointer displayed at any one time.
	In parallel programs, there is an instruction pointer for every process.</p>

	<p>The PTP debugger shows one instruction pointer for
	<i>every group of processes at the same location</i>. In the following example, there are processes suspended
	at three different locations in the program.</p>

	<p><img src="images/06mip.png"></p>

	<p><i>The group of processes represented by an instruction pointer
	is not necessarily the same as a process set.</i></p>

	<p>Different markers are used to indicate the types of processes stopped at that location (the different types will be discussed below):</p>
	<ul>
	<li><p><img src="images/06ipReg.png">Registered processes marker</p></li>
	<li><p><img src="images/06ipUnreg.png">Un-registered processes marker</p></li>
	<li><p><img src="images/06ipMult.png">Marker indicating a combination of registered and un-registered processes</p></li>
	</ul>

	<p>Placing the mouse over an instruction pointer provides additional information about the processes suspended at that location:</p>
	<p><img src="images/06cipHover.png"></p>

	<h2 id="reg">Process Registration and the Debug View</h2>

	<p>Once processes of a parallel job have been suspended, it is often desirable to obtain more detailed information about an individual process.
	In order to do this, a particular process must first be <i>registered</i>. Once a process is registered it's threads and stack frames appear in
	the Debug view. By selecting the stack frame in this view, detailed information about the local variables can be obtained in the Variables view.</p>

	<p>Any number of processes can be registered, and processes can be registered or un-registered at any time. To register a process, double-click its
	process icon in the Parallel Debug view. A black box will be shown around the process icon to indicate that it has been registered. At the same time,
	the process will appear in the Debug view.</p>

	<p><img src="images/06reg1.png"></p>

	<p>To un-register a process, double-click on the same process icon. The box disappears, and the process is removed from the debug view.</p>

	<p>The Debug view also provides a set of debug commands (resume, pause, step over, etc.) that apply to the <i>currently selected process</i> in the view.
	This provides a convenient means of controlling individual processes.</p>

	<h2 id="finish">Terminating Execution</h2>
	At the end of a debug session, it is necessary to terminate the execution of the job. To do this, click on the terminate icon
	<img src="images/06terminateAll.png"> in the Parallel Debug view. Note that the terminate icon in the Debug view
	<img src="images/06terminate.png"> will only terminate the currently selected process in that view.

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