Programming Models @ BSC

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DLB Downloads

You can get a DLB stable package from the links below, or visit https://github.com/bsc-pm/dlb for the most up to date version. Check also our installation guide.

Version 3.6.0-beta1

Added

  • Initial support for GPU TALP metrics (includes NVIDIA and AMD support)
  • Added a new and more robust support for MPI Fortran 2008 bindings
  • New binary dlb_mpi to check affinity in MPI environments
  • Flags --gpu-affinity and --uuid for dlb and dlb_mpi to show GPU visibility
  • New instrumentation events for OMPT callbacks
  • New API DLB_DROM_SetProcessMaskStr to set masks using a human-readable input

Changed

  • --talp-output-file now creates missing directories if able

Fixed

  • Fixed TALP Global region not being started if no MPI or OpenMP
  • Replace PAPI reset calls with regular reads to improve performance
  • Add several PAPI init checks
  • Fixed several LeWI features in async mode

Version 3.5.3 (2025-09-08)

Added

  • Added documentation for DLB_DROM_FLAGS_NONE argument
  • Other minor documentation corrections

Changed

  • Remove MPI Fortran 2008 bindings check at configure time; bindings remain disabled pending new interception method

Fixed

  • Fixed compilation error with GCC 15
  • Fixed errors in the OpenMP thread manager during initialization
  • Fixed some OpenMP thread manager logic for SMT systems
  • Fixed bug in DLB_MonitoringRegionReset; region was not being removed from an internal list of open regions
  • Stop instrumentation after MPI_Finalize to avoid unwanted interactions with external libraries

Version 3.5.2 (2025-05-02)

Added

  • Add dlb_mpi binary to display CPU affinity and MPI rank
  • Add more verbose messages for OMPT events
  • Add implicit-task-end OMPT event to add consistency to Cray OpenMP

Fixed

  • Fixed several errors with CPU topology parsing
  • Removed deprecated options and struct members in examples

Version 3.5.1 (2025-03-05)

Added

  • Add --disable-sphinx-doc, --disable-doxygen, and --disable-pandoc to configure script to disable the automatic detection of each tool

Fixed

  • Fixed several bugs with CPU affinity masks detection and parsing
  • POP metrics conditional printing improved for MPI/OpenMP detection
  • Fix some compilation errors with clang-19, nvc, and nvfortran
  • Improved documentation in user guide
  • Several other minor fixes

Version 3.5.0 (2024-12-03)

Added

  • Asynchronous support for classic LeWI
  • Several SMT enhancements for LeWI policies
  • Allowed to override lewi classic/mask with --lewi-affinity
  • TALP POP metrics now includes experimental OpenMP hybrid metrics
  • TALP global region is now exposed in the API
  • TALP-Pages, a new tool for Continuous Performance Monitoring in static HTML pages
  • Add flag --talp-region-select to filter active regions
  • SLURM integration via dlb_taskset
  • CMake config for other projects to link with DLB
  • Several examples and documentation reworked
  • DLB version information can be accessed though the API

Changed

  • --talp-summary has been simplified and now pop-metrics also includes raw metrics if using an output file, and process metrics now includes node identifiers
  • TALP now only stores monitoring regions in shared memory if --talp-external-profiler is set
  • TALP output structure has been reworked
  • TALP main region is now called “Global”

Fixed

  • LeWI mask now correctly supports threads blocked in MPI calls while pinned to multiple CPUs
  • Add sanity checks for hardware counters in TALP
  • Print JSON and CSV files in the proper locale

Deprecated

  • --talp-summary values for pop-raw and node are deprecated
  • TALP output format XML is now deprecated
  • --talp-regions-per-proc flag is deprecated for a new experimental --shm-size-multiplier flag
  • Several fields in dlb_monitor_t are now deprecated
  • Several fields in dlb_pop_metrics_t are now deprecated
  • DLB_MonitoringRegionGetMPIRegion deprecated in favor of DLB_MonitoringRegionGetGlobal
  • DLB_Stats_GetCpuStateIdle functionality no longer provided
  • DLB_Stats_GetCpuStateOwned functionality no longer provided
  • DLB_Stats_GetCpuStateGuested functionality no longer provided

Version 3.4.1 (2024-08-16)

Fixed

  • Fix an error in the shared memory alignment that was causing segmentation faults when compiling with -march=native
  • Avoid registering role shifting callbacks for other non-related OpenMP thread managers
  • Update examples with supported options
  • Fix some parameters in the Fortran’08 interface
  • Be more resilient if PAPI fails to initialize
  • Enhance compatibility in other systems
  • Quote string names in csv files
  • Several other minor fixes

Version 3.4 (2023-12-22)

Added

  • PAPI support for TALP metrics
  • libdlb_mpic.so and libdlb_mpic_*.so are C MPI only libraries that may be built using --enable-c-mpi-library at configure time
  • Functions to reset, stop, start and report monitoring regions now accept the special argument DLB_MPI_REGION for the implicit region
  • Function DLB_TALP_QueryPOPNodeMetrics for third-party applications to query pop metrics. Requires --talp-external-profiler.
  • Named barriers and several API functions to manage them
  • Added --lewi-barrier and --lewi-barrier-select to fine-tune which barriers activate LeWI.
  • Added --lewi-color to select specific key only for LeWI

Changed

  • libdlb_mpif.so and libdlb_mpif_*.so are no longer built by default, only if --enable-fortran-mpi-library is set at configure time
  • Flag --quiet now only suppresses INFO and VERBOSE, added new flag --silent to keep the old functionality to suppress all messages
  • Refactor DLB_TALP_CollectNodeMetrics to DLB_TALP_CollectPOPNodeMetrics and add communication efficiency
  • TALP now appends to CSV files if they already exist

Fixed

  • Fixed wrong generated code for MPI_Initialized and MPI_Finalized

Deprecated

  • --lewi-ompt no longer accepts “mpi” nor “aggressive” as values. Automatic LeWI via synchronization calls is now done with --lewi-mpi-calls for MPI and --lewi-barrier or --lewi-barrier-select for DLB Barriers.

Version 3.3.1 (2023-05-18)

Fixed

  • Fixed wrong generated code for MPI_Initialized and MPI_Finalized

Version 3.3 (2023-05-15)

Added

  • Free agent and Role-shift OMPT thread managers to support LeWI with both implementations
  • Flag --ompt-thread-manager to select which OpenMP implementation to use
  • MPI Fortran 2008 bindings
  • TALP flag to generate file in different output formats --talp-output-file
  • New TALP collective functions to gather and compute metrics: DLB_TALP_CollectPOPMetrics and DLB_TALP_CollectNodeMetrics

Changed

  • libdlb_mpi.so and libdlb_mpi_*.so have now both C and Fortran MPI symbols

Fixed

  • Fixed DROM pre-initialization if child had empty cpuset affinity
  • Fixed --lewi-max-parallelism
  • Fixed several TALP bugs
  • Fixed some finalization errors during MPI finalize
  • Fixed cpuset parsing when provided a non-contiguous mask

Version 3.2 (2022-03-16)

Added

  • Flag --verbose to enable all verbose modes
  • Flag --talp-summary=pop-raw to print raw POP metrics
  • Flag --lewi-respect-cpuset to allow LeWI to use CPUs not yet registered

Changed

  • DROM can now steal all CPUs from one process
  • DROM can now inherit a subset of CPUs from other process
  • DLB_DROM_SetProcessMask to oneself does not longer require a DLB_pollDROM
  • DLB_Lend in OpenMP applications now invokes the OpenMP runtime to change the number of threads

Fixed

  • Fixed TALP regions enabled or registered only on some processes
  • Fixed minor option parsing

Version 3.1 (2021-11-05)

Added

  • New --lewi-mpi-calls value: none
  • New MPI runtime version check during initialization
  • Experimental meson build files
  • Add better support for getting/setting process mask from own process

Changed

  • Enable --barrier by default
  • Rename --lewi-mpi to its opposite: --lewi-keep-one-cpu, and change the default behavior
  • Rename --talp-summary=app to --talp-summary=pop-metrics and make it the default value
  • Rename TALP to Tracking Application Live Performance
  • CPU priority now follows a better topology order
  • Properly clean up shared memory during initialization

Fixed

  • Fixed several TALP issues
  • Improves support for OMPT
  • Proper shared memory clean up if running under dlb_run

Deprecated

  • Python viewer scripts are no longer installed

Version 3.0 (2021-01-15)

Added

  • New TALP module: Tracking Application Low-level Performance
  • TALP Monitoring Regions for user-defined regions
  • Allow processes to attach to / detach from the Barrier module
  • Improve the verbose messages for some modules
  • Allow partial instrumentation of some events
  • Man pages for DLB commands

Changed

  • DLB library now always prints to stderr, DLB binaries may still use stdout
  • Dropped support for binary mask old format 1000b in favor of 0b0001
  • DLB_ARGS variable now takes precedence over DLB_Init argument

Fixed

  • Some callbacks not being invoked when the action involved some successful actions and some others not allowed
  • Several DROM inconsistencies
  • Several minor fixes
  • Minor documentation fixes

Version 2.1 (2019-07-15)

Added

  • OMPT full support
  • Add function to API: DLB_UnsetMaxParallelism
  • New binary dlb_run to preinit masks, needed for OMPT applications
  • Improved dlb_shm --list output
  • New verbose option affinity to print hardware information
  • Add option --quiet to silent all info and warning messages
  • New test mechanism based on LIT

Changed

  • DLB_Lend does no longer keeps the current CPU
  • PreInit service now handles the timeout if the synchronous flag is provided
  • DROM now accepts registering and setting empty masks
  • Verbose options now affect all library versions

Fixed

  • Added some mechanisms to clean shared memories when the program aborts
  • Fixed several race conditions with the asynchronous messages
  • Fixed an issue where --lewi-affinity was being ignored
  • Adapt Fortran headers to be fixed-form compatible

Version 2.0 (2017-12-21)

Added

  • Callback system
  • API for subprocesses
  • New interaction mode choice (synchronous as it was before, or asynchronous)
  • Doxygen HTML and man pages documentation
  • Test coverage support
  • OMPT experimental support

Changed

  • API reworked
  • A petition of a CPU now registers the process into a CPU petition queue. If this CPU becomes available, DLB can schedule which process will acquire it
  • A petition of an unspecified CPU registers the process into a global petition queue, this queue has less priority than the CPU queue
  • DLB acquire now does not schedule because it forces the acquisition, DLB Borrow does scheduling but only looks for idle CPUs and never creates a CPU request
  • DLB options print format reworked, DLB_ARGS is now used to pass options to DLB.
  • Fortran Interface is now a Fortran include with ISO C bindings.
  • Shared Memory synchronization mechanism is now managed using a pthread spinlock
  • DROM services now use the same shmem handler so no need to call DLB_Init and DLB_DROM_Init
  • DROM services Get/Set process mask are now asynchronous functions

Fixed

  • Test suite now follows a Unit Testing approach and does not need undocumented external tools
  • Several minor bugs
  • PreInit service now correctly handles environment variables and allows forks

Deprecated

  • DLB_MASK is no longer used, only registered CPUs may be used by other processes
  • DLB_DROM_GetCpus service has been removed
  • LB_OPTION type of environment variables is deprecated

Version 1.3 (2017-07-12)

Added

  • Shared Memory consistency checks upon registration
  • The binary dlb_taskset can now be used to launch processes under DLB
  • Service DLB_Barrier to perform a barrier between all processes in the node
  • DLB Services now return an error code
  • New User Option LB_PRIORITY to manage how CPUs are distributed according to HW locality
  • Add services for DROM to PreInit and PostFinalize to manage process that will fork/exec
  • Add services to check if the process mask needs to be changed

Changed

  • Refactor policy based Shared Memory into two general purpose cpuinfo and procinfo
  • DROM interface is now considered stable. External processes can manage the CPU ownership of DLB processes
  • DLB options are now parsed through the environment variable DLB_ARGS

Fixed

  • Several minor bugs

Deprecated

  • Signal handler feature is no longer supported

Version 1.2 (2016-12-23)

Changed

  • Improved User Guide
  • Improved configure script and macros

Fixed

  • Compatibility with gcc6
  • Compatibility with icc17
  • Compatibility with C11 standard
  • Several minor bugs

Version 1.1 (2016-02-04)

Added

  • Policy Autonomous Lewi Mask to micro-manage each thread individually
  • DLB services to init/finalize without MPI support
  • DLB services to enable/disable or mark a serial/parallel sections of code
  • DLB service to modify User Options during program execution
  • New library independent from MPI
  • Binary dlb_shm to manage Shared Memory from CLI
  • Binary dlb_taskset to manage processes’ mask from CLI
  • BG/Q support
  • Add LB_MASK environment variable to specify a DLB_MASK common to all processes
  • Experimental implementation of DLB_Stats interface
  • Experimental implementation of DLB_DROM interface
  • Signal handler feature to clean up DLB on termination
  • In-code Doxygen documentation
  • User guide using Sphynx generator
  • Distributable examples

Changed

  • Replace IPC with POSIX Shared Memory
  • Replace Shared Memory synchronization mechanism from semaphores to pthread mutexes
  • Shared Memory creation is now decentralized from rank 0 and it will be created when necessary
  • Shared Memory internal structure reworked to host information about ownership and guesting of CPUs
  • CPUs from DLB_MASK can guest any process, but they will not have an owner
  • Improve support for detection of Shared Memory runtimes

Fixed

  • Compatibility with gcc 4.4 and 4.5
  • Compatibility with MPI-3 standard
  • Fotran interfaces now use the correct types
  • Several minor bugs

Version 1.0 (2013-12-11)

Added

  • DLB Interface
  • MPI Interception Interface
  • User options configured by environment variables LB_*
  • Lend When Idle algorithm implementation
  • DPD
  • Extrae instrumentation
  • Paraver configs for DLB events
  • Inter-Process Communication (IPC) Shared Memory
  • Inter-Process Communication (IPC) Sockets
  • Thread binding interface
  • LeWI policies to support SMPSS and OpenMP
  • LeWI mask policy to support OmpSs
  • RaL and PERaL policies for redistribution of resources
  • HWLOC optional dependency to query HW info
  • Scheduling decisions based on HW locality
  • Binary dlb

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