merge Fred and Henri description of the same stuff

[simgrid.git] / doc / doxygen / options.doc

diff --git a/doc/doxygen/options.doc b/doc/doxygen/options.doc
index edb44a1..1e39ada 100644 (file)
--- a/doc/doxygen/options.doc
+++ b/doc/doxygen/options.doc
@@ -518,6 +518,21 @@ second) under which the execution chunks are not reported to the
 simulation kernel (default value: 1e-6). Please note that in some
 circonstances, this optimization can hinder the simulation accuracy.
 
 simulation kernel (default value: 1e-6). Please note that in some
 circonstances, this optimization can hinder the simulation accuracy.
 

+ In some cases, however, one may wish to disable simulation of
+application computation. This is the case when SMPI is used not to
+simulate an MPI applications, but instead an MPI code that performs
+"live replay" of another MPI app (e.g., ScalaTrace's replay tool,
+various on-line simulators that run an app at scale). In this case the
+computation of the replay/simulation logic should not be simulated by
+SMPI. Instead, the replay tool or on-line simulator will issue
+"computation events", which correspond to the actual MPI simulation
+being replayed/simulated. At the moment, these computation events can
+be simulated using SMPI by calling internal smpi_execute*() functions.
+
+To disable the benchmarking/simulation of computation in the simulated
+application via this runtime automatic switching, the variable \b
+smpi/privatize_global_variables should be set to no
+

 \subsection options_smpi_timing Reporting simulation time
 
 Most of the time, you run MPI code through SMPI to compute the time it
 \subsection options_smpi_timing Reporting simulation time
 
 Most of the time, you run MPI code through SMPI to compute the time it


@@ -555,7 +570,7 @@ To avoid this, several options are possible :
   linking is advised (but not with the simgrid library, to avoid replicating 
   its own global variables). 
 
   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
 
 
   should be set to yes
 
 


@@ -576,6 +591,7 @@ simulate the behavior of most of the existing MPI libraries. The \b smpi/coll_se
 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 .
 
 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 .
 

+

 \section options_generic Configuring other aspects of SimGrid
 
 \subsection options_generic_path XML file inclusion path
 \section options_generic Configuring other aspects of SimGrid
 
 \subsection options_generic_path XML file inclusion path


@@ -638,12 +654,14 @@ It can be done by using XBT. Go to \ref XBT_log for more details.
 
 - \c surf/nthreads: \ref options_model_nthreads
 
 
 - \c surf/nthreads: \ref options_model_nthreads
 

+- \c smpi/simulation_computation: \ref options_smpi_bench

 - \c smpi/running_power: \ref options_smpi_bench
 - \c smpi/display_timing: \ref options_smpi_timing
 - \c smpi/cpu_threshold: \ref options_smpi_bench
 - \c smpi/async_small_thres: \ref options_model_network_asyncsend
 - \c smpi/send_is_detached: \ref options_model_smpi_detached
 - \c smpi/coll_selector: \ref options_model_smpi_collectives
 - \c smpi/running_power: \ref options_smpi_bench
 - \c smpi/display_timing: \ref options_smpi_timing
 - \c smpi/cpu_threshold: \ref options_smpi_bench
 - \c smpi/async_small_thres: \ref options_model_network_asyncsend
 - \c smpi/send_is_detached: \ref options_model_smpi_detached
 - \c smpi/coll_selector: \ref options_model_smpi_collectives

+- \c smpi/privatize_global_variables: \ref options_smpi_global

 
 - \c path: \ref options_generic_path
 - \c verbose-exit: \ref options_generic_exit
 
 - \c path: \ref options_generic_path
 - \c verbose-exit: \ref options_generic_exit