----------------------------------------------------------------------------
-SimGrid (3.26.1) NOT RELEASED YET (v3.27 expected March 20. 2021, 09:37 UTC)
+SimGrid (3.29.1) NOT RELEASED YET (v3.30 expected December 21. 2021, 15:59 UTC)
+
+Main user-visible changes:
+ - The SimDag API for the simulation of the scheduling of Directed Acyclic
+ Graphs has been dropped. It was marked as deprecated for a couple of years.
+ We finally complete the implementation of what has been called SimDag++
+ internally, i.e., porting the different features of SimDag on top of S4U.
+ The new way to simulate the execution of dependent activities directly by
+ maestro (without any other actor) is details in the examples/cpp/dag-* series
+ of examples.
+ - The removal of SimDag led us to also remove the export to Jedule files that
+ was tightly coupled to SimDag. The instrumentation of DAG simulation is still
+ possible through the regular instrumentation API based on the Paje format.
+ - We also dropped the old and clumsy Lua bindings to create platforms in a
+ programmatic way. It can be done in C++ in a much cleaner way now, which
+ motivates this suppression.
-User-visible changes:
- - Removed some option aliases that were deprecated since v3.23 (June 2019)
- - 'verbose-exit' is now 'debug/verbose-exit'
- - 'simix/breakpoint' is now 'debug/breakpoint'
- - 'clean-atexit' is now 'debug/clean-atexit'
+S4U:
+ - Introduce on_X_cb() functions for all signals, to attach a new
+ callback to the signal X. The signal variables are now hidden and
+ only these functions should be used.
+ Rationale: this enables the usual deprecation schema where functions
+ remain for 4 releases if we need to modify the signals, while the
+ current code with the signal variables directly visible prevents any
+ smooth transition.
+ - New function: Engine::run_until(date), to split the simulation.
+ - New signal: Activity::on_veto, to detect when an activity fails to start.
+ - New function: Engine::track_vetoed_activities() to interrupt run()
+ when an activity fails to start, and to keep track of such activities.
+ Please see the corresponding example for more info.
+
+SMPI:
+ - Dynamic costs for MPI operations: New API to allow users to dynamically
+ change injected costs for MPI_Recv, MPI_Send and MPI_Isend operations.
+ Alternative for smpi/or, smpi/os and smpi/ois configuration options.
+
+Documentation:
+ - New section: "SimGrid MPI calibration of a Grid5000 cluster"
+ presenting how to properly calibrate MPI communications in SimGrid.
+ - Complete and reword the platform section, which is now completed.
+
+Python:
+ - Thread contexts are used by default with Python bindings. Other kinds of
+ contexts revealed unstable, specially starting with pybind11 v2.8.0.
+
+Fixed bugs (FG#.. -> FramaGit bugs; FG!.. -> FG merge requests)
+ (FG: issues on Framagit; GF: issues on GForge; GH: issues on GitHub)
+ - FG#95: Wrong computation time for multicore execution after pstate change
+ - FG#97: Wrong computation time for ptask+multicore+pstates
+ - FG#99: Weird segfault when not sealing an host
+
+----------------------------------------------------------------------------
+
+SimGrid (3.29) October 7. 2021
+
+The "Ask a stupid question" release.
+
+We wish that every user ask one question about SimGrid to celebrate.
+On Mattermost, Stack Overflow or using the issues tracker.
+
+
+New modeling features:
+ - Non-linear resource sharing, modeling resources whose performance heavily degrades with contention:
+ - The total capacity may be updated dynamically through a callback
+ and depends mainly on the number of concurrent flows.
+ - Examples (both cpp and python): io-degradation, network-nonlinear, exec-cpu-nonlinear
+
+ - Dynamic factors: model variability in the speed of activities
+ - Each action can now have a factor that affects its progression.
+ This multiplicative factor is applied when updating the amount of work
+ remaining, thereby an activity with factor=0.5 only uses half of the
+ instantaneous power/bandwidth it is allocated and will appear twice
+ slower than what it actually consumes.
+ - This can be used to model a overhead (e.g., there is a 20 bytes
+ header in a 480 bytes TCP packet so the factor 0.9583) but the novelty
+ is this factor can now easily be adjusted depending on activity's and
+ resources characteristics.
+ - This existed for network (e.g., the effective bandwidth depends
+ on the message in SMPI piecewise-linear network model) but it is now
+ more general (the factor may depend on the source and destination and
+ thus account to different behaviors for intra-node communications and
+ extra-node communications) and is available for CPUs (e.g., if you
+ want to model an affinity as in the "Unrelated Machines" problem in
+ scheduling) and disks (e.g., if you want to model a stochastic
+ capacity) too.
+ - For that, resources can be provided with a callback that computes
+ the activity factor when creating the action.
+ - Example: examples/cpp/exec-cpu-factors
+ - The same mechanism is also available for the latency, which
+ allows to easily introduce complex variability patterns.
+
+Python:
+ - Added support to programmatic platform creation in Python.
+ Example: examples/python/clusters-multicpu
+
+S4U:
+ - Disk and Host now have a set_sharing_policy() too, for non-linear sharing.
+ This can only be set through the API, not through XML files.
+
+SMPI:
+ - TI Tracing/Replay:
+ - Multiple fixes to ensure reproducibility of tracing
+ - scan/excan can now be replayed
+ - wait action now uses ranks and not pid, as the other ones.
+ - smpi/init and smpi/finalization-barrier are now valid for replays.
+ - exit() is now intercepted by SMPI to avoid premature shutdown of
+ simulation. First non 0 return codes is returned as simulation return
+ code.
+
+Documentation:
+ * New section "Release Notes" documenting recent and current developments.
+ * New section "Modeling I/O: the realistic way" presenting how to properly model disks in SimGrid.
+ * Improvements in API Reference for C++ and Python interfaces.
+
+ns-3 model:
+ - Make wifi creation compatible with ns-3 version 3.34 too.
+
+Fixed bugs (FG#.. -> FramaGit bugs; FG!.. -> FG merge requests)
+ (FG: issues on Framagit; GF: issues on GForge; GH: issues on GitHub)
+ - FG#78: Multiple fixes for SMPI replay:
+ - TI tracing of allotallv/w was outputting wrong values
+ - MPI_LOGICAL in fortran is actually 32 bits wide, and not 8.
+ - FG#77: Search feature of doc is broken (update sphinx theme version)
+----------------------------------------------------------------------------
+
+SimGrid (3.28) July 14. 2021
+
+The Victoriadagarna Release.
+
+New features:
+ - C++ platform interface: Users can now describe their platform directly in C++.
+ This provides greatly flexibility and performance improvement for complex
+ platforms. Main features:
+ - Fat-Tree/DragonFly/Torus composing: allows you to create clusters of
+ "zones", instead of single hosts. This feature enables the description
+ of clusters with complex hosts, composed of several CPUs, GPUs, etc.
+ - StarZone: new zone with a Star-like topology. The routes are defined
+ as a set of links used to communicate from node to everybody (node<->ALL).
+ - Split-Duplex links: auxiliary method to create split-duplex links in
+ the platform, easing its utilisation. It automatically creates both UP
+ and DOWN links (similarly as done in XML).
+ - Please refer to the documentation and the examples included:
+ e.g. examples/cpp/clusters-multicpu/ and examples/platforms/*.cpp.
+ - New plugin: Producer-Consumer with monitor. Just requires to include the
+ include/simgrid/plugins/ProducerConsumer.hpp header to be used. See the
+ associated example (examples/cpp/plugin-prodcons).
+
+S4U:
+ - New: s4u::Comm::wait_all_for() (like s4u::Comm::wait_all, but with a timeout),
+ s4u::Io::wait_any(), s4u::Io::wait_any_for().
+ - Methods test_all/test_any/wait_all/wait_any in s4u now take their vector
+ parameter by reference, instead of a pointer.
+ - Fixed a bug where Activity::wait_for() killed the activity on timeout.
+ Explicitly cancel the activity to get back to previous behavior.
+ - New: Link::set_concurrency_limit() to limit the amount of concurrent flows.
+
+SMPI:
+ - The default SMPI compiler flags are no more taken from the environment.
+ They can be explicitly set through cmake parameters SMPI_C_FLAGS,
+ SMPI_CXX_FLAGS, or SMPI_Fortran_FLAGS.
+ - New options:
+ --cfg=smpi/finalization-barrier: which can be used to add
+ a barrier inside MPI_Finalize. This can help for some codes which cleanup
+ data attached to a process, but still used in other SMPI processes.
+ --cfg=smpi/errors-are-fatal: True by default, behaves like if MPI_ERRORS_RETURN
+ is active when set to false, to keep going after a small error
+ --cfg=smpi/pedantic: True by default. Do not report some harmless MPI errors
+ which may or may not be problematic in the end.
+ - Sampling:
+ - fix behaviour, as maximum iteration count could be ignored
+ - add SMPI_SAMPLE_LOCAL_TAG and SMPI_SAMPLE_GLOBAL_TAG macros, to allow user to
+ use sampling when the same kernel is called with a different set of parameters
+ which have an impact on the timing.
+ - realloc is now intercepted, to be coherent, as malloc/calloc/free were already.
+ It should now work with smpi/auto-shared-malloc-thresh.
+ - Improve error handling and reporting in multiple places
+ - Improve correctness checks on the MPI code.(MPI_Op and MPI_Datatype
+ validity checks, truncated messages are now an error, return errors
+ when explicitely deleted handles are reused, ...)
+ - RMA: multiple fixes and stability improvements.
+ - analysis (-analyze flag in smpirun):
+ - SMPI can now report buffer leaks as well as MPI handles leaks,
+ if code was compiled without SMPI_NO_OVERRIDE_MALLOC.
+ - if -trace-call-location is used when compiling, SMPI can report
+ origin of leaked handles/buffers
+ - group leaks by type/origin in output message if possible
+ - New implemented MPI calls: MPI_Comm_test_inter
+
+Models:
+ - Changed internal implementation of bandwidth factors in network models.
+ Models affected: CM02, LV08 (default), SMPI, IB.
+ Configuration affected: "network/bandwidth-factors" and "smpi/bw-factors".
+ Bandwidth factors are applied to communications to describe that users
+ cannot use 100% of the available bandwidth. For example, the default network model,
+ LV08, applies a factor of 0.97 to the bandwidth. In older versions, this
+ behavior was implemented by limiting the bandwidth available in the LMM
+ system for this flow. This may give the false impression that there is
+ bandwidth available for other flows due to its underutilization, especially
+ for the dynamic bandwidth factors used in SMPI models.
+ To avoid this, we have modified the implementation so that each flow uses the
+ maximum physical bandwidth according to the LMM system.
+ However, the actual throughput of the flow seen by the user is defined by
+ the physical bandwidth multiplied by the bandwidth factor.
+ This change impacts on the simulation results for all network models on
+ which we have bandwidth factors configured.
+ *****************************************
+ *DO NOT MIX 3.28 RESULTS WITH OLDER ONES*
+ *****************************************
+ This change may impact on the timing of your simulation results.
+ Take care when comparing simulations from different SimGrid's
+ versions. Sorry for the inconvenience.
+ - Dynamic network factors: users can configure a callback to define
+ the network factors dynamically. This API is available at
+ simgrid::kernel::resource::NetworkModelIntf.
+ - Users have access to complete information about the current communication
+ to decide which factor to apply. This includes: message size, source and
+ destination hosts, links and zones traversed.
+ - Dynamic factors for both latency and bandwidth.
+ - For more details, see the example in (examples/cpp/network-factors).
+ - Plugin host_energy: the "watt_off" and "watt_per_state" host properties,
+ deprecated since version 3.24, are no longer supported. Instead, use
+ "wattage_off" and "wattage_per_state".
+
+XBT:
+ - xbt_assert is not disabled anymore, even when built with enable_debug=off.
+
+Documentation:
+ - New tutorial: Model-checking and formal assessment
+ - New sections: "Demystifying the routing" and "C++ platforms"
+ - Update and improve the part on visualization in MPI and Algo tutorials.
+ - Improve the section on routing: how to define it, how it's used internally
+ - Fix many issues, broken links and missing references in doxygen and Sphinx
+
+LUA:
+ - Lua platform files are deprecated. Their support will be dropped after v3.31.
+
+Simix:
+ - Legacy functions deprecated in this release: SIMIX_get_clock(), SIMIX_run().
+
+Fixed bugs (FG#.. -> FramaGit bugs; FG!.. -> FG merge requests)
+ (FG: issues on Framagit; GF: issues on GForge; GH: issues on GitHub)
+ - FG#47: Complete and fix tests from teshuite/s4u/activity-lifecycle
+ - FG#64: Configuring smpi/IB-penalty-factors
+ - FG#67: Running computation concurrently with MPI_Iallreduce
+ - FG#69: Tutorial misleading users of pre-v3.26 versions of SimGrid
+ - FG#71: Segmentation fault on invalid gw_src/gw_dst
+ - GH#322: Issue when an actor kills his host vm
+
+----------------------------------------------------------------------------
+
+SimGrid (3.27) March 29. 2021
+
+The Ragnar Release (anniversary of the siege of Paris by Vikings in 845)
+
+Main user-visible changes:
+ - All functions marked as deprecated for one year were removed.
- Removed all that was related to the "Storage" type in all APIs and bindings.
"Disks" have been introduced more than a year ago to replace them for the better.
It's time to finish this replacement.
- - Model iteration order may change simulations.
- *****************************************
- *DO NOT MIX 3.27 RESULTS WITH OLDER ONES*
- *****************************************
- The order in which the different models (CPU, network, disk, etc) are
- solved internally has changed in this version. Although rare (no current
- test raises the problem), this change can result in slightest different simulations
- results. Take care when comparing simulations from different SimGrid's
- versions. Sorry for the inconvenience.
- - SMPI API break from previous version: MPI global handles (predefined datatypes,
+ - SMPI ABI breaks from previous version: MPI global handles (predefined datatypes,
ops, COMM_WORLD) are now defined differently, and can be used in initializers,
avoiding "initializer element is not constant" errors with some codes. Please be
careful to recompile your MPI codes if switching to this new SimGrid version.
- Network model ns-3 now requires version ns-3.28 or higher.
+ - Removed some option aliases that were deprecated since v3.23 (June 2019)
+ - 'verbose-exit' is now 'debug/verbose-exit'
+ - 'simix/breakpoint' is now 'debug/breakpoint'
+ - 'clean-atexit' is now 'debug/clean-atexit'
S4U:
- New functions: Comm::sendto_{init,async} to initiate a communication
- New section: Programming API of logs.
- New section: Getting realistic results
- New section: Examples of SMPI Usage
- - New part: SimGrid's Intenal, with a section on Design goals
+ - 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. This may be nothing,
- but if the number is high it could be a problem. To display more information
- about the type of leaked handle, option --cfg=smpi/list-leaks:n. will display
- the n first leaked pointers and their types. Known issue: MPI_Cancel usage
- may trigger handle leaks in SMPI.
- Using smpirun with -wrapper "valgrind --leak-check=full --track-origins=yes"
- can provide more information to help locate precisely the leaks.
- - Memory allocations analysis: MPI codes using malloc/calloc to
- allocate memory, and not compiled with SMPI_NO_OVERRIDE_MALLOC, can use
- smpi/display-analysis option to show at the end of execution the amount of
- memory allocated through these calls, and locate the most expensive one.
- This helps finding the targets for manual memory sharing, or the threshold
- to use for smpi/auto-shared-malloc-thresh option.
+ - 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,
- Codevault bhtree_mpi
Model checker:
- - Only initialze the Dwarf parser when needed, saving 10 seconds in most cases.
+ - Only initialize the Dwarf parser when needed, saving 10 seconds in most cases.
- Start to overhaul the implementation to modernize it (still ongoing).
XBT:
