+S4U:
+ - New functions: Comm::sendto_{init,async} to initiate a communication
+ on between two (possibly remote) hosts.
+ - Define new template functions Mailbox::get_unique(), returning a std::unique_ptr.
+ - Functions Mailbox::get() and Mailbox::get_async() are now templated with the
+ type of the pointee. Untyped functions are deprecated. Use Mailbox::get<void>()
+ or Mailbox::get_async<void>() if you really want to play with void*.
+ - Unify the interface of Activity::on_{start/activity}
+ - New function: Comm::get_dst_data()
+ - New function: Comm::set_payload_size() to set the amount of bytes to simulate.
+
+Models:
+ - ptask should now work better with multicore hosts (FG#37).
+ - Internal cleanups and refactoring around activities, to prepare for SimDAG++.
+ - Internal cleanups and refactoring around models, to prepare for programmatic
+ platform creation.
+ - Modernize our tests of the performance models
+
+Documentation:
+ - User manual:
+ - New section: Configuring the logs from the command line.
+ - New section: Programming API of logs.
+ - New section: Getting realistic results
+ - New section: Examples of SMPI Usage
+ - New part: SimGrid's Internals, with a section on Design goals
+ - Move back to the classical Breathe tool chain, and fix many small glitches.
+
+SMPI:
+ - Handle leak checking: SMPI will now display a message if MPI handles are still
+ present at the end of a simulation. Option smpi/list-leaks:n will display the n
+ first leaked pointers and their types.
+ - smpi/display-allocs option : Display Memory allocations analysis, with hints
+ about the largest allocations. This only works for allocations with malloc/calloc
+ and not compiled with SMPI_NO_OVERRIDE_MALLOC
+ - "-analyze" option in smpirun will activate smpi/display-allocs and smpi/display-timing
+ - New implemented MPI calls: MPI_File_set_size, MPI_Aint_add, MPI_Aint_diff,
+ MPI_Type_get_extent_x, MPI_Type_get_true_extent_x, MPI_Status_set_elements_x
+ - Support for MPI C++ datatypes (MPI_CXX_BOOL, MPI_CXX_FLOAT_COMPLEX,
+ MPI_CXX_DOUBLE_COMPLEX, MPI_CXX_LONG_DOUBLE_COMPLEX)
+ - Replay now opens and parses the trace file only once for all ranks when possible.
+ - Misc fixes:
+ - better handling of MPI_PROC_NULL
+ - MPI_Group_incl was broken in some cases
+ - PAPI tracing now fixed
+ - MPI_Errhandlers are properly handled for MPI_COMM_WORLD
+ - SMPI will now fail properly when receive size < sent size, instead of
+ just setting MPI_ERR_TRUNCATE and keep going.
+ - Proxy Apps ( https://framagit.org/simgrid/SMPI-proxy-apps ):
+ - Remove useless build patches and split build/run patches on the page
+ - Build in parallel when possible
+ - Test on yum-based systems
+ - New nightly tested Proxy-apps:
+ - OpenMPI mpi-test-suite
+ - Coral MCB, LSMS, Qbox, CLOMP
+ - ECP/Mantevo Cloverleaf3D, Ember
+ - Codevault bhtree_mpi
+
+Model checker:
+ - Only initialize the Dwarf parser when needed, saving 10 seconds in most cases.
+ - Start to overhaul the implementation to modernize it (still ongoing).
+
+XBT:
+ - Drop simgrid::xbt::demangle(). Please use boost::core::demangle() instead.
+ - Drop xbt_dynar_cursor_rm(), xbt_dynar_search_or_negative(),
+ xbt_str_split_quoted(), xbt_str_split_quoted_in_place().
+ - Deprecate xbt_dynar_to_array().
+ - When an exception occurs in kernel mode, display both the actor and kernel stacks.
+
+C binding and interface:
+ - Rename (lowercase) functions sg_actor_get_PID, sg_actor_get_PPID, sg_actor_by_PID.
+ - Constness requirement has been lowered for parameter argv of sg_actor_start()
+ and sg_actor_create() It's now (char* const*). The previous version is still
+ available as sg_actor_start_() and sg_actor_create_().
+
+Fixed bugs (FG#.. -> FramaGit bugs; FG!.. -> FG merge requests)
+ (FG: issues on Framagit; GF: issues on GForge; GH: issues on GitHub)
+ - FG#37: Parallel tasks are limited to 1 core per host
+ - FG#62: Running "smpirun -replay" on large networks
+ - FG!46: Fix a few potential memory leaks in SMPI colls
+ - GH#343: Wrong consumed energy when an exec timeouts
+
+----------------------------------------------------------------------------
+
+SimGrid (3.26) December 15. 2020
+
+The Release release (the French lockdown was eased today).
+
+Important user-visible changes:
+ - SimGrid now requires a compiler with C++14 support.
+ Sibling projects should upgrade their FindSimgrid.cmake
+ - Surf precision default value is now 1e-9, instead of 1e-5. This was changed as
+ several users had difficulties to understand issues when using high bandwidth or
+ small latency events. The new value was already the default for SMPI and
+ should not cause too much performance hit. It can change some simulation
+ timings if simulation was skipping a lot of small events (which was actually
+ an issue per see). The old value can be restored with --cfg=surf/precision:1e-5.
+ - On some network models (L07, CM02, LV08), an implicit loopback link is created
+ for local communication. Default bandwidth was 500MBps and latency was 15µs,
+ which was rather bad. Default values have been changed to 10GBps and 0 latency.
+ Options network/loopback-lat and network/loopback-bw have been added to adapt
+ these values if needed. Network and routing models already providing separate
+ loopbacks (clusters and such) are not impacted by this change.
+ - SMPI now adds 16 bytes of header to each message sent, in order to simulate
+ metadata that are added to each MPI message by MPI libraries (tag,
+ src/dest, and communicator information). This may change simulation times
+ for very small message sizes, but should be more realistic.
+
+New features:
+ - New routing 'WiFi' that makes it easier to specify a wifi network zone.
+ - New plugins: wifi_energy and link_load. See the associated examples.
+ - New examples: wifi networks, and communication suspend.
+
+General:
+ - LTO is now enabled for Intel/clang compilers.
+ - LTO behavior on GCC can be parameterized using LTO_EXTRA_FLAG in cmake.
+ Setting it to "auto" will use all available cores, while setting it to n will
+ use n cores to speedup link step (usage: cmake -DLTO_EXTRA_FLAG=4).
+ - Remove obsolete runtime option 'contexts/parallel-threshold'.
+ - Runtime option 'tracing/msg/process' renamed to 'tracing/actor'. The old name
+ has been kept for compatibility.
+ - Finally remove obsolete snake_case() aliases for runtime options.
+ - Further improve the documentation.
+
+S4U:
+ - the on_exit() of each actor is also executed when the simulation deadlocks.
+ - New functions: s4u::Activity:: suspend(), resume() and is_suspended()
+ An example is provided for s4u::Comm but it should work with Exec and Io.
+
+SMPI:
+ - Update proxy apps coverage of new ECP apps: 60+ apps now tested nightly on
+ https://framagit.org/simgrid/SMPI-proxy-apps
+ - MPI/IO: supports names starting with "./"
+ - Fortran: many MPI/IO bindings, support for MPI_UB/LB, C MPI_INT/FLOAT/DOUBLE
+ datatypes.
+ - smpicc/cxx/ff/f90 now will actually perform definition checks at link time. When
+ building shared libraries, this may cause issues, so environment variable
+ SMPI_NO_UNDEFINED_CHECK can be added to disable this.
+ - most temporary files should now be created in /tmp dir (or equivalent).
+ If this one does not allow execution of code (noexec flag), this may cause issues.
+ Please use another tmp directory (using TMPDIR or equivalent system variable)
+ in this case.
+
+Model-Checker:
+ - A large refactoring is ongoing, but this should be transparent for users so far.
+
+XBT:
+ - Drop xbt_str_split().
+
+C binding and interface:
+ - The return type of the sg_actor_on_exit() callbacks is now 'void'
+ (int value was previously ignored)
+ - Many C functions were renamed to follow a common naming style
+ (sg_object_get_something and sg_object_set_something). As usual, the deprecated
+ names are kept until version 3.30.