lmm_solve (experts only; check the code for more info).
If you compiled SimGrid accordingly, you can use packet-level network
-simulators as network models (see \ref pls). In that case, you have
+simulators as network models (see \ref pls_ns3). In that case, you have
two extra models, described below, and some \ref options_pls "specific
additional configuration flags".
- - \b NS3: Network pseudo-model using the NS3 tcp model instead of an
- analytic model
+ - \b NS3: Network pseudo-model using the NS3 tcp model
Concerning the CPU, we have only one model for now:
- \b Cas01: Simplistic CPU model (time=size/power)
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
(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_thresh 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.
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)
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
\section options_tracing Configuring the tracing subsystem
-The \ref tracing "tracing subsystem" can be configured in several
+The \ref outcomes_vizu "tracing subsystem" can be configured in several
different ways depending on the nature of the simulator (MSG, SimDag,
SMPI) and the kind of traces that need to be obtained. See the \ref
tracing_tracing_options "Tracing Configuration Options subsection" to
- 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
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
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
+\subsection options_model_smpi_adj_file smpi/comp-adjustment-file: Slow-down or speed-up parts of your code.
+
+This option allows you to pass a file that contains two columns: The first column
+defines the section that will be subject to a speedup; the second column is the speedup.
+
+For instance:
+
+\verbatim
+"start:stop","ratio"
+"exchange_1.f:30:exchange_1.f:130",1.18244559422142
+\endverbatim
+
+The first line is the header - you must include it.
+The following line means that the code between two consecutive MPI calls on
+line 30 in exchange_1.f and line 130 in exchange_1.f should receive a speedup
+of 1.18244559422142. The value for the second column is therefore a speedup, if it is
+larger than 1 and a slow-down if it is smaller than 1. Nothing will be changed if it is
+equal to 1.
+
+Of course, you can set any arbitrary filenames you want (so the start and end don't have to be
+in the same file), but be aware that this mechanism only supports @em consecutive calls!
+
+\note
+ Please note that you must pass the \b -trace-call-location flag to smpicc
+ or smpiff, respectively! This flag activates some macro definitions in our
+ mpi.h / mpi.f files that help with obtaining the call location.
+
+\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
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.
\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 .
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/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_comm_determinism
+- \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 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/comp-adjustment-file: \ref options_model_smpi_adj_file
- \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