+SMPI provides 2 algorithms for this feature. The first one, called \c
+local, allocates one bloc per call to SMPI_SHARED_MALLOC() in your
+code (each call location gets its own bloc) and this bloc is shared
+amongst all MPI ranks. This is implemented with the shm_* functions
+to create a new POSIX shared memory object (kept in RAM, in /dev/shm)
+for each shared bloc.
+
+With the \c global algorithm, each call to SMPI_SHARED_MALLOC()
+returns a new adress, but it only points to a shadow bloc: its memory
+area is mapped on a 1MiB file on disk. If the returned bloc is of size
+N MiB, then the same file is mapped N times to cover the whole bloc.
+At the end, no matter how many SMPI_SHARED_MALLOC you do, this will
+only consume 1 MiB in memory.
+
+You can disable this behavior and come back to regular mallocs (for
+example for debugging purposes) using \c "no" as a value.
+
+If you want to keep private some parts of the buffer, for instance if these
+parts are used by the application logic and should not be corrupted, you
+can use SMPI_PARTIAL_SHARED_MALLOC(size, offsets, offsets_count).
+
+As an example,
+
+\code{.C}
+ mem = SMPI_PARTIAL_SHARED_MALLOC(500, {27,42 , 100,200}, 2);
+\endcode
+
+will allocate 500 bytes to mem, such that mem[27..41] and mem[100..199]
+are shared and other area remain private.
+
+Then, it can be deallocated by calling SMPI_SHARED_FREE(mem).
+
+When smpi/shared-malloc:global is used, the memory consumption problem
+is solved, but it may induce too much load on the kernel's pages table.
+In this case, you should use huge pages so that we create only one
+entry per Mb of malloced data instead of one entry per 4k.
+To activate this, you must mount a hugetlbfs on your system and allocate
+at least one huge page:
+
+\code{.sh}
+ mkdir /home/huge
+ sudo mount none /home/huge -t hugetlbfs -o rw,mode=0777
+ sudo sh -c 'echo 1 > /proc/sys/vm/nr_hugepages' # echo more if you need more
+\endcode
+
+Then, you can pass the option --cfg=smpi/shared-malloc-hugepage:/home/huge
+to smpirun to actually activate the huge page support in shared mallocs.
+
+\subsection options_model_smpi_wtime smpi/wtime: Inject constant times for calls to MPI_Wtime
+
+\b Default value: 0
+
+By setting this option, you can control the amount of time a process sleeps
+when MPI_Wtime() is called; this is important, because SimGrid normally only
+advances the time while communication is happening and thus,
+MPI_Wtime will not add to the time, resulting in a deadlock if used as a
+break-condition.
+
+Here is an example:
+
+\code{.unparsed}
+ while(MPI_Wtime() < some_time_bound) {
+ ...
+ }
+\endcode
+
+If the time is never advanced, this loop will clearly never end as MPI_Wtime()
+always returns the same value. Hence, pass a (small) value to the smpi/wtime
+option to force a call to MPI_Wtime to advance the time as well.
+
+
+\section options_generic Configuring other aspects of SimGrid
+
+\subsection options_generic_clean_atexit Cleanup before termination
+
+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
+is registered and will clean up some variables and terminate/cleanup the tracing.
+
+TODO: Add when this should be used.
+
+\subsection options_generic_path Profile files' search path
+
+It is possible to specify a list of directories to search into for the
+trace files (see @ref pf_trace) by using the \b path configuration
+item. To add several directory to the path, set the configuration
+item several times, as in \verbatim
+--cfg=path:toto --cfg=path:tutu
+\endverbatim
+
+\subsection options_generic_breakpoint Set a breakpoint
+
+\verbatim
+--cfg=simix/breakpoint:3.1416
+\endverbatim
+
+This configuration option sets a breakpoint: when the simulated clock reaches
+the given time, a SIGTRAP is raised. This can be used to stop the execution and
+get a backtrace with a debugger.
+
+It is also possible to set the breakpoint from inside the debugger, by writing
+in global variable simgrid::simix::breakpoint. For example, with gdb:
+
+\verbatim
+set variable simgrid::simix::breakpoint = 3.1416
+\endverbatim
+
+\subsection options_generic_exit Behavior on Ctrl-C
+
+By default, when Ctrl-C is pressed, the status of all existing
+simulated processes is displayed before exiting the simulation. This is very useful to debug your
+code, but it can reveal troublesome in some cases (such as when the
+amount of processes becomes really big). This behavior is disabled
+when \b verbose-exit is set to 0 (it is to 1 by default).
+
+\subsection options_exception_cutpath Truncate local path from exception backtrace