--- /dev/null
+/*! \page outcomes_vizu Visualization and Statistical Analysis
+
+SimGrid comes with an extensive support to trace and register what
+happens during the simulation, so that it can be either visualized or
+statistically analysed after the simulation.
+
+This tracing is widely used to observe and understand the behavior of
+parallel applications and distributed algorithms. Usually, this is
+done in a two-step fashion: the user instruments the application and
+the traces are analyzed after the end of the execution. The analysis
+can highlights unexpected behaviors, bottlenecks and sometimes can be
+used to correct distributed algorithms. The SimGrid team has
+instrumented the library in order to let users trace their simulations
+and analyze them. This part of the user manual explains how the
+tracing-related features can be enabled and used during the
+development of simulators using the SimGrid library.
+
+\section instr_category_functions Tracing categories functions
+
+The SimGrid library is instrumented so users can trace the platform
+utilization using MSG, SimDAG and SMPI interfaces. It registers how
+much power is used for each host and how much bandwidth is used for
+each link of the platform. The idea with this type of tracing is to
+observe the overall view of resources utilization in the first place,
+especially the identification of bottlenecks, load-balancing among
+hosts, and so on.
+
+Another possibility is to trace resource utilization by
+categories. Categorized resource utilization tracing gives SimGrid
+users to possibility to classify MSG and SimDAG tasks by category,
+tracing resource utilization for each of the categories. The functions
+below let the user declare a category and apply it to tasks. <em>The
+tasks that are not classified according to a category are not
+traced</em>. Even if the user does not specify any category, the
+simulations can still be traced in terms of resource utilization by
+using a special parameter that is detailed below (see section \ref
+tracing_tracing_options).
+
+\li \c TRACE_category(const char *category)
+\li \c TRACE_category_with_color(const char *category, const char *color)
+\li \c MSG_task_set_category(msg_task_t task, const char *category)
+\li \c MSG_task_get_category(msg_task_t task)
+\li \c SD_task_set_category(SD_task_t task, const char *category)
+\li \c SD_task_get_category(SD_task_t task)
+
+\section instr_mark_functions Tracing marks functions
+\li \c TRACE_declare_mark(const char *mark_type)
+\li \c TRACE_mark(const char *mark_type, const char *mark_value)
+
+\section instr_uservariables_functions Tracing user variables functions
+
+For hosts:
+
+\li \c TRACE_host_variable_declare(const char *variable)
+\li \c TRACE_host_variable_declare_with_color(const char *variable, const char *color)
+\li \c TRACE_host_variable_set(const char *host, const char *variable, double value)
+\li \c TRACE_host_variable_add(const char *host, const char *variable, double value)
+\li \c TRACE_host_variable_sub(const char *host, const char *variable, double value)
+\li \c TRACE_host_variable_set_with_time(double time, const char *host, const char *variable, double value)
+\li \c TRACE_host_variable_add_with_time(double time, const char *host, const char *variable, double value)
+\li \c TRACE_host_variable_sub_with_time(double time, const char *host, const char *variable, double value)
+
+For links:
+
+\li \c TRACE_link_variable_declare(const char *variable)
+\li \c TRACE_link_variable_declare_with_color(const char *variable, const char *color)
+\li \c TRACE_link_variable_set(const char *link, const char *variable, double value)
+\li \c TRACE_link_variable_add(const char *link, const char *variable, double value)
+\li \c TRACE_link_variable_sub(const char *link, const char *variable, double value)
+\li \c TRACE_link_variable_set_with_time(double time, const char *link, const char *variable, double value)
+\li \c TRACE_link_variable_add_with_time(double time, const char *link, const char *variable, double value)
+\li \c TRACE_link_variable_sub_with_time(double time, const char *link, const char *variable, double value)
+
+For links, but use source and destination to get route:
+
+\li \c TRACE_link_srcdst_variable_set(const char *src, const char *dst, const char *variable, double value)
+\li \c TRACE_link_srcdst_variable_add(const char *src, const char *dst, const char *variable, double value)
+\li \c TRACE_link_srcdst_variable_sub(const char *src, const char *dst, const char *variable, double value)
+\li \c TRACE_link_srcdst_variable_set_with_time(double time, const char *src, const char *dst, const char *variable, double value)
+\li \c TRACE_link_srcdst_variable_add_with_time(double time, const char *src, const char *dst, const char *variable, double value)
+\li \c TRACE_link_srcdst_variable_sub_with_time(double time, const char *src, const char *dst, const char *variable, double value)
+
+\section tracing_tracing_options Tracing configuration Options
+
+To check which tracing options are available for your simulator, you
+can just run it with the option \verbatim --help-tracing \endverbatim
+to get a very detailed and updated explanation of each tracing
+parameter. These are some of the options accepted by the tracing
+system of SimGrid, you can use them by running your simulator with the
+<b>--cfg=</b> switch:
+
+\li <b>\c
+tracing
+</b>:
+ Safe switch. It activates (or deactivates) the tracing system.
+ No other tracing options take effect if this one is not activated.
+\verbatim
+--cfg=tracing:yes
+\endverbatim
+
+\li <b>\c
+tracing/categorized
+</b>:
+ It activates the categorized resource utilization tracing. It should
+ be enabled if tracing categories are used by this simulator.
+\verbatim
+--cfg=tracing/categorized:yes
+\endverbatim
+
+\li <b>\c
+tracing/uncategorized
+</b>:
+ It activates the uncategorized resource utilization tracing. Use it if
+ this simulator do not use tracing categories and resource use have to be
+ traced.
+\verbatim
+--cfg=tracing/uncategorized:yes
+\endverbatim
+
+\li <b>\c
+tracing/filename
+</b>:
+ A file with this name will be created to register the simulation. The file
+ is in the Paje format and can be analyzed using Viva or Paje visualization
+ tools. More information can be found in these webpages:
+ <a href="http://github.com/schnorr/viva/">http://github.com/schnorr/viva/</a>
+ <a href="http://github.com/schnorr/pajeng/">http://github.com/schnorr/pajeng/</a>
+\verbatim
+--cfg=tracing/filename:mytracefile.trace
+\endverbatim
+ If you do not provide this parameter, the trace file will be named simgrid.trace.
+
+\li <b>\c
+tracing/smpi
+</b>:
+ This option only has effect if this simulator is SMPI-based. Traces the MPI
+ interface and generates a trace that can be analyzed using Gantt-like
+ visualizations. Every MPI function (implemented by SMPI) is transformed in a
+ state, and point-to-point communications can be analyzed with arrows.
+\verbatim
+--cfg=tracing/smpi:yes
+\endverbatim
+
+\li <b>\c
+tracing/smpi/group
+</b>:
+ This option only has effect if this simulator is SMPI-based. The processes
+ are grouped by the hosts where they were executed.
+\verbatim
+--cfg=tracing/smpi/group:yes
+\endverbatim
+
+\li <b>\c
+tracing/smpi/computing
+</b>:
+ This option only has effect if this simulator is SMPI-based. The parts external
+to SMPI are also outputted to the trace. Provides better way to analyze the data automatically.
+\verbatim
+--cfg=tracing/smpi/computing:yes
+\endverbatim
+
+\li <b>\c
+tracing/smpi/internals
+</b>:
+ This option only has effect if this simulator is SMPI-based. Display internal communications
+happening during a collective MPI call.
+\verbatim
+--cfg=tracing/smpi/internals:yes
+\endverbatim
+
+\li <b>\c
+tracing/smpi/display-sizes
+</b>:
+ This option only has effect if this simulator is SMPI-based. Display the sizes of the messages
+exchanged in the trace, both in the links and on the states. For collective, size means the global size of data sent by the process in general.
+\verbatim
+--cfg=tracing/smpi/display-sizes:yes
+\endverbatim
+
+\li <b>\c
+tracing/smpi/sleeping
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+tracing/smpi/format
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+tracing/smpi/format/ti-one-file
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+tracing/msg/vm
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+tracing/msg/process
+</b>:
+ This option only has effect if this simulator is MSG-based. It traces the
+ behavior of all categorized MSG processes, grouping them by hosts. This option
+ can be used to track process location if this simulator has process migration.
+\verbatim
+--cfg=tracing/msg/process:yes
+\endverbatim
+
+\li <b>\c
+tracing/buffer
+</b>:
+ This option put some events in a time-ordered buffer using the
+ insertion sort algorithm. The process of acquiring and releasing
+ locks to access this buffer and the cost of the sorting algorithm
+ make this process slow. The simulator performance can be severely
+ impacted if this option is activated, but you are sure to get a trace
+ file with events sorted.
+\verbatim
+--cfg=tracing/buffer:yes
+\endverbatim
+
+\li <b>\c
+tracing/onelink-only
+</b>:
+This option changes the way SimGrid register its platform on the trace
+file. Normally, the tracing considers all routes (no matter their
+size) on the platform file to re-create the resource topology. If this
+option is activated, only the routes with one link are used to
+register the topology within an AS. Routes among AS continue to be
+traced as usual.
+\verbatim
+--cfg=tracing/onelink-only:yes
+\endverbatim
+
+\li <b>\c
+tracing/disable-link
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+tracing/disable-power
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+tracing/disable-destroy
+</b>:
+Disable the destruction of containers at the end of simulation. This
+can be used with simulators that have a different notion of time
+(different from the simulated time).
+\verbatim
+--cfg=tracing/disable-destroy:yes
+\endverbatim
+
+\li <b>\c
+tracing/basic
+</b>:
+Some visualization tools are not able to parse correctly the Paje file format.
+Use this option if you are using one of these tools to visualize the simulation
+trace. Keep in mind that the trace might be incomplete, without all the
+information that would be registered otherwise.
+\verbatim
+--cfg=tracing/basic:yes
+\endverbatim
+
+\li <b>\c
+tracing/comment
+</b>:
+Use this to add a comment line to the top of the trace file.
+\verbatim
+--cfg=tracing/comment:my_string
+\endverbatim
+
+\li <b>\c
+tracing/comment-file
+</b>:
+Use this to add the contents of a file to the top of the trace file as comment.
+\verbatim
+--cfg=tracing/comment-file:textual_file.txt
+\endverbatim
+
+\li <b>\c
+tracing/precision
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+tracing/platform
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+tracing/platform/topology
+</b>:
+TODO
+\verbatim
+TODO
+\endverbatim
+
+\li <b>\c
+viva/categorized
+</b>:
+ This option generates a graph configuration file for Viva considering
+ categorized resource utilization.
+\verbatim
+--cfg=viva/categorized:graph_categorized.plist
+\endverbatim
+
+\li <b>\c
+viva/uncategorized
+</b>:
+ This option generates a graph configuration file for Viva considering
+ uncategorized resource utilization.
+\verbatim
+--cfg=viva/uncategorized:graph_uncategorized.plist
+\endverbatim
+
+Please pass \verbatim --help-tracing \endverbatim to your simulator
+for the updated list of tracing options.
+
+\section tracing_tracing_example_parameters Case studies
+
+Some scenarios that might help you decide which tracing options
+you should use to analyze your simulator.
+
+\li I want to trace the resource utilization of all hosts
+and links of the platform, and my simulator <b>does not</b> use
+the tracing API. For that, you can run a uncategorized trace
+with the following parameters (it will work with <b>any</b> Simgrid
+simulator):
+\verbatim
+./your_simulator \
+ --cfg=tracing:yes \
+ --cfg=tracing/uncategorized:yes \
+ --cfg=tracing/filename:mytracefile.trace \
+ --cfg=viva/uncategorized:uncat.plist
+\endverbatim
+
+\li I want to trace only a subset of my MSG (or SimDAG) tasks.
+For that, you will need to create tracing categories using the
+<b>TRACE_category (...)</b> function (as explained above),
+and then classify your tasks to a previously declared category
+using the <b>MSG_task_set_category (...)</b>
+(or <b>SD_task_set_category (...)</b> for SimDAG tasks). After
+recompiling, run your simulator with the following parameters:
+\verbatim
+./your_simulator \
+ --cfg=tracing:yes \
+ --cfg=tracing/categorized:yes \
+ --cfg=tracing/filename:mytracefile.trace \
+ --cfg=viva/categorized:cat.plist
+\endverbatim
+
+
+\section tracing_tracing_example Example of Instrumentation
+
+A simplified example using the tracing mandatory functions.
+
+\verbatim
+int main (int argc, char **argv)
+{
+ MSG_init (&argc, &argv);
+
+ //(... after deployment ...)
+
+ //note that category declaration must be called after MSG_create_environment
+ TRACE_category_with_color ("request", "1 0 0");
+ TRACE_category_with_color ("computation", "0.3 1 0.4");
+ TRACE_category ("finalize");
+
+ msg_task_t req1 = MSG_task_create("1st_request_task", 10, 10, NULL);
+ msg_task_t req2 = MSG_task_create("2nd_request_task", 10, 10, NULL);
+ msg_task_t req3 = MSG_task_create("3rd_request_task", 10, 10, NULL);
+ msg_task_t req4 = MSG_task_create("4th_request_task", 10, 10, NULL);
+ MSG_task_set_category (req1, "request");
+ MSG_task_set_category (req2, "request");
+ MSG_task_set_category (req3, "request");
+ MSG_task_set_category (req4, "request");
+
+ msg_task_t comp = MSG_task_create ("comp_task", 100, 100, NULL);
+ MSG_task_set_category (comp, "computation");
+
+ msg_task_t finalize = MSG_task_create ("finalize", 0, 0, NULL);
+ MSG_task_set_category (finalize, "finalize");
+
+ //(...)
+
+ MSG_clean();
+ return 0;
+}
+\endverbatim
+
+\section tracing_tracing_analyzing Analyzing SimGrid Simulation Traces
+
+A SimGrid-based simulator, when executed with the correct parameters
+(see above) creates a trace file in the Paje file format holding the
+simulated behavior of the application or the platform. You have
+several options to analyze this trace file:
+
+- Dump its contents to a CSV-like format using `pj_dump` (see <a
+ href="https://github.com/schnorr/pajeng/wiki/pj_dump">PajeNG's wiki
+ on pj_dump</a> and more generally the <a
+ href="https://github.com/schnorr/pajeng/">PajeNG suite</a>) and use
+ gnuplot to plot resource usage, time spent on blocking/executing
+ functions, and so on. Filtering capabilities are at your hand by
+ doing `grep`, with the best regular expression you can provide, to
+ get only parts of the trace (for instance, only a subset of
+ resources or processes).
+
+- Derive statistics from trace metrics (the ones built-in with any
+ SimGrid simulation, but also those metrics you injected in the trace
+ using the TRACE module) using the <a
+ href="http://www.r-project.org/">R project</a> and all its
+ modules. You can also combine R with <a
+ href="http://ggplot2.org/">ggplot2</a> to get a number of high
+ quality plots from your simulation metrics. You need to `pj_dump`
+ the contents of the SimGrid trace file to use R.
+
+- Visualize the behavior of your simulation using classic space/time
+ views (gantt-charts) provided by the <a
+ href="https://github.com/schnorr/pajeng/">PajeNG suite</a> and any
+ other tool that supports the <a
+ href="http://paje.sourceforge.net/download/publication/lang-paje.pdf">Paje
+ file format</a>. Consider this option if you need to understand the
+ causality of your distributed simulation.
+
+- Visualize the behavior of your simulation with treemaps (specially
+ if your simulation has a platform with several thousand resources),
+ provided by the <a href="http://github.com/schnorr/viva/">Viva</a>
+ visualization tool. See <a
+ href="https://github.com/schnorr/viva/wiki">Viva's wiki</a> for
+ further details on what is a treemap and how to use it.
+
+- Correlate the behavior of your simulator with the platform topology
+ with an interactive, force-directed, and hierarchical graph
+ visualization, provided by <a
+ href="http://github.com/schnorr/viva/">Viva</a>. Check <a
+ href="https://github.com/schnorr/viva/wiki">Viva's wiki</a> for
+ further details. This <a
+ href="http://hal.inria.fr/hal-00738321/">research report</a>,
+ published at ISPASS 2013, has a detailed description of this
+ visualization technique.
+
+- You can also check our online <a
+ href="http://simgrid.gforge.inria.fr/tutorials.html"> tutorial
+ section</a> that contains a dedicated tutorial with several
+ suggestions on how to use the tracing infrastructure. Look for the
+ SimGrid User::Visualization 101 tutorial.
+
+- Ask for help on the <a
+ href="mailto:simgrid-user@lists.gforge.inria.fr">simgrid-user@lists.gforge.inria.fr</a>
+ mailing list, giving us a detailed explanation on what your
+ simulator does and what kind of information you want to trace. You
+ can also check the <a
+ href="http://lists.gforge.inria.fr/pipermail/simgrid-user/">mailing
+ list archive</a> for old messages regarding tracing and analysis.
+
+\subsection tracing_viva_analysis Viva Visualization Tool
+
+This subsection describe some of the concepts regarding the <a
+href="http://github.com/schnorr/viva/">Viva Visualization Tool</a> and
+its relation with SimGrid traces. You should refer to Viva's website
+for further details on all its visualization techniques.
+
+\subsubsection tracing_viva_time_slice Time Slice
+
+The analysis of a trace file using the tool always takes into account
+the concept of the <em>time-slice</em>. This concept means that what
+is being visualized in the screen is always calculated considering a
+specific time frame, with its beggining and end timestamp. The
+time-slice is configured by the user and can be changed dynamically
+through the window called <em>Time Interval</em> that is opened
+whenever a trace file is being analyzed. Users are capable to select
+the beggining and size of the time slice.
+
+\subsubsection tracing_viva_graph Hierarchical Graph View
+
+%As stated above (see section \ref tracing_tracing_analyzing), one
+possibility to analyze SimGrid traces is to use Viva's graph view with
+a graph configuration to customize the graph according to the
+traces. A valid graph configuration (we are using the non-XML <a
+href="http://en.wikipedia.org/wiki/Property_list">Property List
+Format</a> to describe the configuration) can be created for any
+SimGrid-based simulator using the
+<em>--cfg=viva/uncategorized:graph_uncategorized.plist</em> or
+<em>--cfg=viva/categorized:graph_categorized.plist</em> (if the
+simulator defines resource utilization categories) when executing the
+simulation.
+
+\subsubsection basic_conf Basic Graph Configuration
+
+The basic description of the configuration is as follows:
+\verbatim
+{
+ node = (LINK, HOST, );
+ edge = (HOST-LINK, LINK-HOST, LINK-LINK, );
+\endverbatim
+
+The nodes of the graph will be created based on the <i>node</i>
+parameter, which in this case is the different <em>"HOST"</em>s and
+<em>"LINK"</em>s of the platform used to simulate. The <i>edge</i>
+parameter indicates that the edges of the graph will be created based
+on the <em>"HOST-LINK"</em>s, <em>"LINK-HOST"</em>s, and
+<em>"LINK-LINK"</em>s of the platform. After the definition of these
+two parameters, the configuration must detail how the nodes
+(<em>HOST</em>s and <em>LINK</em>s) should be drawn.
+
+For that, the configuration must have an entry for each of
+the types used. For <em>HOST</em>, as basic configuration, we have:
+
+\verbatim
+ HOST = {
+ type = square;
+ size = power;
+ values = (power_used);
+ };
+\endverbatim
+
+The parameter <em>size</em> indicates which variable from the trace
+file will be used to define the size of the node HOST in the
+visualization. If the simulation was executed with availability
+traces, the size of the nodes will be changed according to these
+traces. The parameter <em>type</em> indicates which geometrical shape
+will be used to represent HOST, and the <em>values</em> parameter
+indicates which values from the trace will be used to fill the shape.
+
+For <em>LINK</em> we have:
+
+\verbatim
+ LINK = {
+ type = rhombus;
+ size = bandwidth;
+ values = (bandwidth_used);
+ };
+}
+\endverbatim
+
+The same configuration parameters are used here: <em>type</em> (with a
+rhombus), the <em>size</em> (whose value is from trace's bandwidth
+variable) and the <em>values</em>.
+
+\subsubsection custom_graph Customizing the Graph Representation
+
+Viva is capable to handle a customized graph representation based on
+the variables present in the trace file. In the case of SimGrid, every
+time a category is created for tasks, two variables in the trace file
+are defined: one to indicate node utilization (how much power was used
+by that task category), and another to indicate link utilization (how
+much bandwidth was used by that category). For instance, if the user
+declares a category named <i>request</i>, there will be variables
+named <b>p</b><i>request</i> and a <b>b</b><i>request</i> (<b>p</b>
+for power and <b>b</b> for bandwidth). It is important to notice that
+the variable <i>prequest</i> in this case is only available for HOST,
+and <i>brequest</i> is only available for LINK. <b>Example</b>:
+suppose there are two categories for tasks: request and compute. To
+create a customized graph representation with a proportional
+separation of host and link utilization, use as configuration for HOST
+and LINK this:
+
+\verbatim
+ HOST = {
+ type = square;
+ size = power;
+ values = (prequest, pcomputation);
+ };
+ LINK = {
+ type = rhombus;
+ size = bandwidth;
+ values = (brequest, bcomputation);
+ };
+\endverbatim
+
+This configuration enables the analysis of resource utilization by MSG
+tasks through the identification of load-balancing issues and network
+bottlenecks, for instance.
+
+*/
