-/*! \page options Step 2: Configure SimGrid
+/*! \page options Configure SimGrid
A number of options can be given at runtime to change the default
SimGrid behavior. For a complete list of all configuration options
"Cpu" to assess energy consumption).
The plugin connects to the code by registering callbacks using
-``surf_callback_register`` (see file ``src/surf/plugins/energy.cpp`` for details).
+``signal.connect(callback)`` (see file ``src/surf/plugins/energy.cpp`` for
+details).
\verbatim
--cfg=plugin:Energy
now).
- \b Full: Full update of remaining and variables. Slow but may be
useful when debugging.
- - items \b network/maxmin_selective_update and
- \b cpu/maxmin_selective_update: configure whether the underlying
+ - items \b network/maxmin-selective-update and
+ \b cpu/maxmin-selective-update: configure whether the underlying
should be lazily updated or not. It should have no impact on the
computed timings, but should speed up the computation.
-It is still possible to disable the \c maxmin_selective_update feature
+It is still possible to disable the \c maxmin-selective-update feature
because it can reveal counter-productive in very specific scenarios
where the interaction level is high. In particular, if all your
communication share a given backbone link, you should disable it:
-without \c maxmin_selective_update, every communications are updated
+without \c maxmin-selective-update, every communications are updated
at each step through a simple loop over them. With that feature
enabled, every communications will still get updated in this case
(because of the dependency induced by the backbone), but through a
The analytical models need to know the maximal TCP window size to take
the TCP congestion mechanism into account. This is set to 20000 by
-default, but can be changed using the \b network/TCP_gamma item.
+default, but can be changed using the \b network/TCP-gamma item.
On linux, this value can be retrieved using the following
commands. Both give a set of values, and you should use the last one,
These factors can be changed through the following option:
\verbatim
-smpi/IB_penalty_factors:"βe;βs;γs"
+smpi/IB-penalty-factors:"βe;βs;γs"
\endverbatim
By default SMPI uses factors computed on the Stampede Supercomputer at TACC, with optimal
\subsubsection options_model_network_crosstraffic Simulating cross-traffic
-As of SimGrid v3.7, cross-traffic effects can be taken into account in
+%As of SimGrid v3.7, cross-traffic effects can be taken into account in
analytical simulations. It means that ongoing and incoming
communication flows are treated independently. In addition, the LV08
model adds 0.05 of usage on the opposite direction for each new
(this configuration item is experimental and may change or disapear)
It is possible to specify a timing gap between consecutive emission on
-the same network card through the \b network/sender_gap item. This
+the same network card through the \b network/sender-gap item. This
is still under investigation as of writting, and the default value is
to wait 10 microseconds (1e-5 seconds) between emissions.
It is possible to specify that messages below a certain size will be sent
as soon as the call to MPI_Send is issued, without waiting for the
correspondant receive. This threshold can be configured through the
-\b smpi/async_small_thres item. The default value is 0. This behavior can also be
+\b smpi/async-small-thresh item. The default value is 0. This behavior can also be
manually set for MSG mailboxes, by setting the receiving mode of the mailbox
with a call to \ref MSG_mailbox_set_async . For MSG, all messages sent to this
mailbox will have this behavior, so consider using two mailboxes if needed.
This options is disabled by default.
-\subsection options_modelchecking_dot_output model-check/dot_output, Dot output
+\subsection options_modelchecking_dot_output model-check/dot-output, Dot output
-If set, the \b model-check/dot_output configuration item is the name of a file
+If set, the \b model-check/dot-output configuration item is the name of a file
in which to write a dot file of the path leading the found property (safety or
liveness violation) as well as the cycle for liveness properties. This dot file
can then fed to the graphviz dot tool to generate an corresponding graphical
\subsection options_modelchecking_max_depth model-check/max_depth, Depth limit
-The \b model-checker/max_depth can set the maximum depth of the exploration
+The \b model-checker/max-depth can set the maximum depth of the exploration
graph of the model-checker. If this limit is reached, a logging message is
sent and the results might not be exact.
\subsection options_modelchecking_comm_determinism Communication determinism
-The \b model-check/communications_determinism and
-\b model-check/send_determinism items can be used to select the communication
+The \b model-check/communications-determinism and
+\b model-check/send-determinism items can be used to select the communication
determinism mode of the model-checker which checks determinism properties of
the communications of an application.
\subsection options_virt_factory Selecting the virtualization factory
-In SimGrid, the user code is virtualized in a specific mecanism
-allowing the simulation kernel to control its execution: when a user
+In SimGrid, the user code is virtualized in a specific mechanism
+that allows the simulation kernel to control its execution: when a user
process requires a blocking action (such as sending a message), it is
interrupted, and only gets released when the simulated clock reaches
the point where the blocking operation is done.
pthreads or windows native threads)
- \b ucontext: fast factory using System V contexts (or a portability
layer of our own on top of Windows fibers)
- - \b raw: amazingly fast factory using a context switching mecanism
+ - \b raw: amazingly fast factory using a context switching mechanism
of our own, directly implemented in assembly (only available for x86
and amd64 platforms for now)
+ - \b boost: This uses the [context implementation](http://www.boost.org/doc/libs/1_59_0/libs/context/doc/html/index.html)
+ of the boost library; you must have this library installed before
+ you compile SimGrid. (On Debian GNU/Linux based systems, this is
+ provided by the libboost-contexts-dev package.)
The only reason to change this setting is when the debugging tools get
fooled by the optimized context factories. Threads are the most
stacks), leading to segfaults with corrupted stack traces.
If you want to push the scalability limits of your code, you might
-want to reduce the \b contexts/stack_size item. Its default value
+want to reduce the \b contexts/stack-size item. Its default value
is 8192 (in KiB), while our Chord simulation works with stacks as small
as 16 KiB, for example. For the thread factory, the default value
is the one of the system, if it is too large/small, it has to be set
Even if you asked several worker threads using the previous option,
you can request to start the parallel execution (and pay the
associated synchronization costs) only if the potential parallelism is
-large enough. For that, set the \b contexts/parallel_threshold
+large enough. For that, set the \b contexts/parallel-threshold
item to the minimal amount of user contexts needed to start the
parallel execution. In any given simulation round, if that amount is
not reached, the contexts will be run sequentially directly by the
- Add the contents of a textual file on top of the trace file as comment:
\verbatim
---cfg=tracing/comment_file:my_file_with_additional_information.txt
+--cfg=tracing/comment-file:my_file_with_additional_information.txt
\endverbatim
Please, use these two parameters (for comments) to make reproducible
Enable this option by adding
\verbatim
---cfg=msg/debug_multiple_use:on
+--cfg=msg/debug-multiple-use:on
\endverbatim
\section options_smpi Configuring SMPI
code, and create an execution task within the simulator to take this
into account. For that, the actual duration is measured on the host
machine and then scaled to the power of the corresponding simulated
-machine. The variable \b smpi/running_power allows to specify the
+machine. The variable \b smpi/running-power allows to specify the
computational power of the host machine (in flop/s) to use when
scaling the execution times. It defaults to 20000, but you really want
to update it to get accurate simulation results.
When the code is constituted of numerous consecutive MPI calls, the
previous mechanism feeds the simulation kernel with numerous tiny
-computations. The \b smpi/cpu_threshold item becomes handy when this
+computations. The \b smpi/cpu-threshold item becomes handy when this
impacts badly the simulation performance. It specifies a threshold (in
seconds) below which the execution chunks are not reported to the
simulation kernel (default value: 1e-6).
\note
- The option smpi/cpu_threshold ignores any computation time spent
+ The option smpi/cpu-threshold ignores any computation time spent
below this threshold. SMPI does not consider the \a amount of these
computations; there is no offset for this. Hence, by using a
value that is too low, you may end up with unreliable simulation
be simulated using SMPI by calling internal smpi_execute*() functions.
To disable the benchmarking/simulation of computation in the simulated
-application, the variable \b
-smpi/simulate_computation should be set to no
+application, the variable \b smpi/simulate-computation should be set to no.
+Equivalently, setting \b smpi/cpu-threshold to -1 also ignores all
+computation.
-\subsection options_model_smpi_bw_factor smpi/bw_factor: Bandwidth factors
+\note
+ This option just ignores the timings in your simulation; it still executes
+ the computations itself. If you want to stop SMPI from doing that,
+ you should check the SMPI_SAMPLE macros, documented in the chapter
+ \ref SMPI_adapting_speed.
+
+\subsection options_model_smpi_bw_factor smpi/bw-factor: Bandwidth factors
The possible throughput of network links is often dependent on the
message sizes, as protocols may adapt to different message sizes. With
1. http://simgrid.gforge.inria.fr/contrib/smpi-calibration-doc.html
2. http://simgrid.gforge.inria.fr/contrib/smpi-saturation-doc.html
-\subsection options_smpi_timing smpi/display_timing: Reporting simulation time
+\subsection options_smpi_timing smpi/display-timing: Reporting simulation time
\b Default: 0 (false)
would take to run it on a platform. But since the
code is run through the \c smpirun script, you don't have any control
on the launcher code, making it difficult to report the simulated time
-when the simulation ends. If you set the \b smpi/display_timing item
+when the simulation ends. If you set the \b smpi/display-timing item
to 1, \c smpirun will display this information when the simulation ends. \verbatim
Simulation time: 1e3 seconds.
\endverbatim
-\subsection options_model_smpi_lat_factor smpi/lat_factor: Latency factors
+\subsection options_model_smpi_lat_factor smpi/lat-factor: Latency factors
The motivation and syntax for this option is identical to the motivation/syntax
-of smpi/bw_factor, see \ref options_model_smpi_bw_factor for details.
+of smpi/bw-factor, see \ref options_model_smpi_bw_factor for details.
-There is an important difference, though: While smpi/bw_factor \a reduces the
+There is an important difference, though: While smpi/bw-factor \a reduces the
actual bandwidth (i.e., values between 0 and 1 are valid), latency factors
increase the latency, i.e., values larger than or equal to 1 are valid here.
1. http://simgrid.gforge.inria.fr/contrib/smpi-calibration-doc.html
2. http://simgrid.gforge.inria.fr/contrib/smpi-saturation-doc.html
-\subsection options_smpi_global smpi/privatize_global_variables: Automatic privatization of global variables
+\subsection options_smpi_global smpi/privatize-global-variables: Automatic privatization of global variables
MPI executables are meant to be executed in separated processes, but SMPI is
executed in only one process. Global variables from executables will be placed
linking is advised (but not with the simgrid library, to avoid replicating
its own global variables).
- To use this runtime automatic switching, the variable \b smpi/privatize_global_variables
+ To use this runtime automatic switching, the variable \b smpi/privatize-global-variables
should be set to yes
immediately. This is different from the threshold detailed in \ref options_model_network_asyncsend
because the message is not effectively sent when the send is posted. SMPI still waits for the
correspondant receive to be posted to perform the communication operation. This threshold can be set
-by changing the \b smpi/send_is_detached item. The default value is 65536.
+by changing the \b smpi/send-is-detached item. The default value is 65536.
\subsection options_model_smpi_collectives Simulating MPI collective algorithms
SMPI implements more than 100 different algorithms for MPI collective communication, to accurately
-simulate the behavior of most of the existing MPI libraries. The \b smpi/coll_selector item can be used
+simulate the behavior of most of the existing MPI libraries. The \b smpi/coll-selector item can be used
to use the decision logic of either OpenMPI or MPICH libraries (values: ompi or mpich, by default SMPI
uses naive version of collective operations). Each collective operation can be manually selected with a
\b smpi/collective_name:algo_name. Available algorithms are listed in \ref SMPI_collective_algorithms .
to sleep increases linearly with the number of previously failed testk.
-\subsection options_model_smpi_use_shared_malloc smpi/use_shared_malloc: Use shared memory
+\subsection options_model_smpi_use_shared_malloc smpi/use-shared-malloc: Factorize malloc()s
\b Default: 1
The C / C++ standard contains a function called \b [atexit](http://www.cplusplus.com/reference/cstdlib/atexit/).
atexit registers callbacks, which are called just before the program terminates.
-By setting the configuration option clean_atexit to 1 (true), a callback
+By setting the configuration option clean-atexit to 1 (true), a callback
is registered and will clean up some variables and terminate/cleanup the tracing.
TODO: Add when this should be used.
A stack guard page is usually used which prevents the stack from
overflowing on other parts of the memory. However this might have a
performance impact if a huge number of processes is created. The
-option \b contexts:guard_size is the number of stack guard pages
+option \b contexts:guard-size is the number of stack guard pages
used. By setting it to 0, no guard pages will be used: in this case,
-you should avoid using small stacks (\b stack_size) as the stack will
+you should avoid using small stacks (\b stack-size) as the stack will
silently overflow on other parts of the memory.
\section options_index Index of all existing configuration options
\b Please \b note: You can also pass the command-line option "--help" and
"--help-cfg" to an executable that uses simgrid.
-- \c clean_atexit: \ref options_generic_clean_atexit
+- \c clean-atexit: \ref options_generic_clean_atexit
- \c contexts/factory: \ref options_virt_factory
-- \c contexts/guard_size: \ref options_virt_parallel
+- \c contexts/guard-size: \ref options_virt_parallel
- \c contexts/nthreads: \ref options_virt_parallel
- \c contexts/parallel_threshold: \ref options_virt_parallel
-- \c contexts/stack_size: \ref options_virt_stacksize
+- \c contexts/stack-size: \ref options_virt_stacksize
- \c contexts/synchro: \ref options_virt_parallel
-- \c cpu/maxmin_selective_update: \ref options_model_optim
+- \c cpu/maxmin-selective-update: \ref options_model_optim
- \c cpu/model: \ref options_model_select
- \c cpu/optim: \ref options_model_optim
- \c maxmin/precision: \ref options_model_precision
-- \c msg/debug_multiple_use: \ref options_msg_debug_multiple_use
+- \c msg/debug-multiple-use: \ref options_msg_debug_multiple_use
- \c model-check: \ref options_modelchecking
- \c model-check/checkpoint: \ref options_modelchecking_steps
-- \c model-check/communications_determinism: \ref options_modelchecking_comm_determinism
-- \c model-check/send_determinism: \ref options_modelchecking_comm_determinism
-- \c model-check/dot_output: \ref options_modelchecking_dot_output
+- \c model-check/communications-determinism: \ref options_modelchecking_comm_determinism
+- \c model-check/dot-output: \ref options_modelchecking_dot_output
- \c model-check/hash: \ref options_modelchecking_hash
- \c model-check/property: \ref options_modelchecking_liveness
-- \c model-check/max_depth: \ref options_modelchecking_max_depth
+- \c model-check/max-depth: \ref options_modelchecking_max_depth
- \c model-check/record: \ref options_modelchecking_recordreplay
- \c model-check/reduction: \ref options_modelchecking_reduction
- \c model-check/replay: \ref options_modelchecking_recordreplay
-- \c model-check/send_determinism: \ref options_modelchecking_sparse_checkpoint
+- \c model-check/send-determinism: \ref options_modelchecking_comm_determinism
- \c model-check/sparse-checkpoint: \ref options_modelchecking_sparse_checkpoint
- \c model-check/termination: \ref options_modelchecking_termination
- \c model-check/timeout: \ref options_modelchecking_timeout
- \c model-check/visited: \ref options_modelchecking_visited
-- \c network/bandwidth_factor: \ref options_model_network_coefs
+- \c network/bandwidth-factor: \ref options_model_network_coefs
- \c network/coordinates: \ref options_model_network_coord
- \c network/crosstraffic: \ref options_model_network_crosstraffic
-- \c network/latency_factor: \ref options_model_network_coefs
-- \c network/maxmin_selective_update: \ref options_model_optim
+- \c network/latency-factor: \ref options_model_network_coefs
+- \c network/maxmin-selective-update: \ref options_model_optim
- \c network/model: \ref options_model_select
- \c network/optim: \ref options_model_optim
- \c network/sender_gap: \ref options_model_network_sendergap
-- \c network/TCP_gamma: \ref options_model_network_gamma
-- \c network/weight_S: \ref options_model_network_coefs
+- \c network/TCP-gamma: \ref options_model_network_gamma
+- \c network/weight-S: \ref options_model_network_coefs
- \c ns3/TcpModel: \ref options_pls
- \c path: \ref options_generic_path
- \c surf/precision: \ref options_model_precision
- \c <b>For collective operations of SMPI, please refer to Section \ref options_index_smpi_coll</b>
-- \c smpi/async_small_thres: \ref options_model_network_asyncsend
-- \c smpi/bw_factor: \ref options_model_smpi_bw_factor
-- \c smpi/coll_selector: \ref options_model_smpi_collectives
-- \c smpi/cpu_threshold: \ref options_smpi_bench
-- \c smpi/display_timing: \ref options_smpi_timing
-- \c smpi/lat_factor: \ref options_model_smpi_lat_factor
-- \c smpi/IB_penalty_factors: \ref options_model_network_coefs
+- \c smpi/async-small-thresh: \ref options_model_network_asyncsend
+- \c smpi/bw-factor: \ref options_model_smpi_bw_factor
+- \c smpi/coll-selector: \ref options_model_smpi_collectives
+- \c smpi/cpu-threshold: \ref options_smpi_bench
+- \c smpi/display-timing: \ref options_smpi_timing
+- \c smpi/lat-factor: \ref options_model_smpi_lat_factor
+- \c smpi/IB-penalty-factors: \ref options_model_network_coefs
- \c smpi/iprobe: \ref options_model_smpi_iprobe
- \c smpi/ois: \ref options_model_smpi_ois
- \c smpi/or: \ref options_model_smpi_or
- \c smpi/os: \ref options_model_smpi_os
-- \c smpi/privatize_global_variables: \ref options_smpi_global
-- \c smpi/running_power: \ref options_smpi_bench
-- \c smpi/send_is_detached_thresh: \ref options_model_smpi_detached
-- \c smpi/simulate_computation: \ref options_smpi_bench
+- \c smpi/privatize-global-variables: \ref options_smpi_global
+- \c smpi/running-power: \ref options_smpi_bench
+- \c smpi/send-is-detached-thresh: \ref options_model_smpi_detached
+- \c smpi/simulate-computation: \ref options_smpi_bench
- \c smpi/test: \ref options_model_smpi_test
-- \c smpi/use_shared_malloc: \ref options_model_smpi_use_shared_malloc
+- \c smpi/use-shared-malloc: \ref options_model_smpi_use_shared_malloc
- \c smpi/wtime: \ref options_model_smpi_wtime
- \c <b>Tracing configuration options can be found in Section \ref tracing_tracing_options</b>.
