* Addition of basic structure
* Reworked categories
* More causal integration additions
* Causal implementation
* Update examples
* delete virtual_speedup files
* Update perfetto submodule to v31.0
* Update dyninst submodule
* Update timemory submodule
* ElfUtils build for libdw
* OMNITRACE_LIKELY and OMNITRACE_UNLIKELY
* Update common lib join
* Examples updates for causal profiling
* config updates with causal options
- OMNITRACE_CAUSAL_FIXED_LINE
- OMNITRACE_CAUSAL_FIXED_SPEEDUP
- OMNITRACE_CAUSAL_FILE
- OMNITRACE_CAUSAL_BINARY_SCOPE
- OMNITRACE_CAUSAL_SOURCE_SCOPE
- version info in banner
- support increments in parse_numeric_range
- fix occasional deadlock in first call to get_config
* PTL general task group
* Always include PID in debug/verbose messages
* Add blocking/unblocking gotchas to runtime init bundle
* CausalState
* thread_data updates
- generic component_bundle_cache
* Improve handling of causal in category_region
* components updates
- backtrace_causal component
- backtrace::get_data member func
- decrease ignore_depth in backtrace::sample(int)
- handle "omnitrace_main" in backtrace::filter_and_patch(...)
- tweak internal thread state scope for pthread_mutex_gotcha wrappers
* simplify tracing get_instrumentation_bundles usage
* sampling updates
- include backtrace_causal component
- disable backtrace_metrics if using causal and not using perfetto
- disable backtrace and backtrace_timestamp when using causal
- post_process_causal
* causal updates
- more checks in blocking_gotcha and unblocking_gotcha start/stop
- miscellaneous overhaul of data
- experiment update
* Remove virtual speedup
* libomnitrace code_object
* causal-profiling test
* libomnitrace library.cpp updates
- handle causal profiling
- fini_bundle
* Disable causal profiling by default
* Updated causal code and example
- example: three execution variants: cpu + rng, cpu, rng
- example: three instrumentation variants: none, omni, coz
- fix blocking gotcha credit
- rework perform_experiment_impl
- get_eligible_address_ranges
- compute_eligible_lines
- support fixed lines/speedups/functions
- update selected_entry to support function mode
- fix causal::delay
- experiment updates
* omnitrace_progress / omnitrace_user_progress
- with accompanying omnitrace_annotated_progress / omnitrace_user_annotated_progress
* Update timemory submodule
* CausalMode
- mode indicated whether causal predictions source be at line-level or function-level
* code_object, config, runtime, sampling, thread_data
- code_object: address_range
- code_object: basic::line_info serialize(), name(), hash()
- config updates
- two signals for causal sampling
- thread_data init fixes
* pthread updates
- pthread_create_gotcha processes delays
- pthread_mutex_gotcha does not wrap pthread_join in causal mode
* backtrace_causal update
- dynamic delay period stats
* main wrapper uses basename of argv[0]
* update elfio submodule
* perf support (currently unused)
* Fix experiment JSON serialization
- static_vector.hpp (unused)
* causal executable + config options updates
- omnitrace-causal exe simplifies running multiple causal configs
- changed the causal config option names
* Support both throughput and latency points
* process-causal-json.py script
- will be used later for testing
* stable_vector
* Rework thread_data
* Improve omnitrace-causal exe
- better verbosity handling
- correct diagnosis of status for child process
- execvpe when only one iteration (debugging)
* Update timemory submodule
* exe --version
- omnitrace, omnitrace-avail, and omnitrace-sample all support --version on command-line
* OMNITRACE_INTERNAL_API + OMNITRACE_{LIKELY,UNLIKELY}
* omnitrace-causal cmake format
* omnitrace config update
- OMNITRACE_CAUSAL_FILE_CLOBBER
* custom exception
- wraps STL exception and gets stacktrace during construction
* exit_gotcha supports _Exit
* use global construct_on_init + max threads
- add some safety when exceeding max # of threads
* update code_object binary filter
- exclude dyninst and tbbmalloc library
* containers: c_array, static_vector, stable_vector
- moved utility::c_array to container::c_array
- created static_vector: std::vector bound to std::array
- created stable_vector: vector with stable references
* grow thread_data when new thread created
* causal updates
- data: improve compute_eligible_lines to ignore lambdas
- data: use new thread_data
- delay: use new thread_data
- experiment: properly support latency points
- experiment: support file clobber
- experiment: ensure non-zero experiment time
- progress_point: use new thread_data
- backtrace_causal: use new thread_data
* Update causal-profiling tests
* fix omnitrace-causal backslash escaping
* process-causal-json script
* restructure causal implementation
- update verbose messages for omnitrace-causal diagnose_status
- migrated causal implementation in sampling.cpp to causal/sampling.cpp
- OMNITRACE_USE_CAUSAL does not require OMNITRACE_USE_SAMPLING
- added Mode::Causal
- causal sampling uses same signals as regular sampling
- moved tracing::thread_init to implementation file
- combined tracing::thread_init and tracing::thread_init_sampling
- added causal/components folder
- pthread_create_gotcha::wrapper_config
- omnitrace_preload checks OMNITRACE_USE_CAUSAL
- updates mode accordingly
* update timemory submodule
* update timemory submodule
* causal example updates
- causal for lulesh
* perf code + utility - helpers
- relocated causal perf code
- placement new when generating unique ptr trait for potentially allocating during sampling
- additions to utility header
- removed previously added helpers.hpp
* update timemory submodule
* Default env variables for omnitrace-causal
- activate OMNITRACE_USE_KOKKOSP, etc.
* update stable_vector and static_vector
- static vector can use atomic for size tracking for thread-safe situations
* update causal example header
- CAUSAL_PROGRESS_NAMED
- use CAUSAL_ prefix for some macros
* Tweak lulesh example
- use CAUSAL_PROGRESS instead of CAUSAL_BEGIN and CAUSAL_END
* omnitrace-sample support for causal mode
- set OMNITRACE_USE_SAMPLING to off when OMNITRACE_MODE=causal
* refactor and cleanup code_object
- scope filter
- fixes to address_range
* overhaul causal data + causal config options
- full support for function and line mode
- support static vector of instruction pointers
- improve line info mapping resolution
- remove thread-locality from miscellanous functions where unnecessary
- causal options for {binary,source,function,fileline} exclusion
* causal experiment, sampling, and backtrace updates
- is_selected + unwind address array
- experiment warning about progress points
- increased buffer size for backtrace_casual sampler
- backtrace_causal only stores IP addresses instead of full unwind info
* category_region updates
- minor refactor
- local_category_region::mark
* Update causal tests
* Bump version to 1.8.0
* omnitrace-causal args + CLOBBER -> RESET
- renamed OMNITRACE_CAUSAL_FILE_CLOBBER to OMNITRACE_CAUSAL_FILE_RESET
- updated omnitrace-causal exe to support recently added configuration options
- other miscellaneous tweaks to data.cpp, experiment.cpp, and sampling.cpp
* Refactor causal and code_object
- code_object.hpp and code_object.cpp moved into binary folder
- causal components namespaced into omnitrace::causal::component
- moved sample_data out of backtrace_causal and into own file
- renamed backtrace_causal to causal::component::backtrace
* preload omnitrace_init + OMNITRACE_DEBUG_MARK
- env OMNITRACE_DEBUG_MARK
- fix omnitrace_init call when LD_PRELOAD-ing omnitrace
* Fix fileline support + line-info output names + experiment log
- line-info log files are prefixed with experiment name
- don't print experiment duration when E2E
- account for fileline scope in analysis
* KokkosP: OMNITRACE_KOKKOSP_NAME_LENGTH_MAX
- config option to limit the name of kokkos tool callbacks
- remove [kokkos] from KokkosP names
* Update causal example
- minor tweaks to decrease probability of overlapping regions in binary
* omnitrace-causal update
- prefix N / Ntot in environment printout
* Miscellaneous updates
- causal::finish_experimenting()
- OMNITRACE_CAUSAL_RANDOM_SEED
- KokkosP causal updates
- exclude some callbacks, make some callbacks unique, etc.
- address_range::operator+=(address_range)
- combine contiguous ranges in binary/analysis.cpp when file, func, line is same and address range is contiguous
- bfd_line_info reads inline info
- wait for perform_experiment_impl to complete
- causal::delay updates
- delay::process checks if experiment is active
- uses threading::get_id()
- experiment scales duration up for larger speedup experiments
- line info samples includes excluded lines
- sampler uses CLOCK_REALTIME
- blocking_gotcha updates
- is no longer fully static
- adds audit routine which sets the postblock value to zero if try/timed routine fails
- category::host was added to causal_throughput_categories_t
- pthread_create_gotcha sets new threads local parent delay
- was using internal value, now uses sequent value
* Causal improvements to KokkosP
* Updates to experiment time scaling
- use stats instead of just max
* binary/link_map.{hpp,cpp}
* update process-causal-json.py
* Folded fileline scope into source scope
* Update documentation
- Add documentation for causal profiling
- Replace 'Omnitrace' with 'OmniTrace' everywhere
* Update causal-helpers.cmake + omnitrace-testing.cmake
- split tests/CMakeLists.txt partially into omnitrace-testing.cmake
* omnitrace/causal.h
- OMNITRACE_CAUSAL_PROGRESS
- OMNITRACE_CAUSAL_PROGRESS_NAMED
- OMNITRACE_CAUSAL_BEGIN
- OMNITRACE_CAUSAL_END
* selected_entry + remove default filters for lambdas and operator()
- selected entry stores range and binary load address
* update process-causal-json.py
* format examples/lulesh/CMakeLists.txt
* causal-helpers find_package(Threads)
* OMNITRACE_KOKKOSP_KERNEL_LOGGER
- was OMNITRACE_KOKKOS_KERNEL_LOGGER
* quiet find of coz-profiler
* Fix rocm_smi exception handling
* Update timemory submodule (binutils)
- fix binutls compile error on some systems
- bump binutils to v2.40
* Fix miscellaneous tests
* OMNITRACE_KOKKOSP_PREFIX
* revert rocm_smi handling
* ElfUtils updates
- default to download version 0.188
- add -Wno-error=null-dereference due to GCC 12 compiler error
* Update causal example
* Remove OMNITRACE_VERBOSE from global workflow envs
* Reliable causal test
* disable compilation of causal perf files
* Remove set_current_selection with unwind stack
* update timemory submodule
* fix for segfault on bionic
- locking in TLS dtor was causing segfault
* remove experiment::is_selected(unwind_stack_t)
* update default init of selected_entry
* Fix for when IP is not offset by load address
* Update CMakeLists.txt
* Miscellaneous updates
- OMNITRACE_WARNING_OR_CI_THROW
- OMNITRACE_REQUIRE
- OMNITRACE_PREFER
- fixed issues with no ASLR
- added load address variable and ipaddr() func to basic/bfd line info
- removed get_basic() from dwarf_line_info
- TIMEMORY_PREFER -> OMNITRACE_PREFER
- removed previously added binary_address and range variables from selected_entry
* Removed superfluous CausalState
* Additional causal tests (lulesh + kokkos)
* filter, prefer, analysis ASLR handling
- removed default filter on cold functions
- fixed OMNITRACE_PREFER
- fixed analysis ASLR handling
* Tweak line-info output
* Removed some superfluous code
- causal/delay
- causal/selected_entry
* Exclude main.cold in function mode
* Update validate-perfetto-proto.py
- account for occasional http errors
* Add sampling test disabling tmp files
* argparser for process-causal-json
- support validation
- support filtering
* Avoid pthread_{lock,unlock} in sampling offload
- use homemade atomic_mutex/atomic_lock since contention will be low and using pthread tools might trigger our wrappers
* Rename process-causal-json.py
- validate-causal-json.py
* rework omnitrace_add_causal_test
- capable of performing validation
- added validation tests
* Fix kokkosp_begin_deep_copy + causal
* Tweak address range in bfd_line_info::read_pc
* Tweak analysis and data IP handling
- look for gaps
* Disable scaling experiment time by speedup
* Revert change in max threads during CI
* binary updates
- significant overhaul of binary analysis implementation
- removed "basic_line_info" and "bfd_line_info" in lieu of "symbol" class
- symbol class has basic BFD info + vector of inlines + vector of dwarf info
* Updated causal to use new binary analysis
- Fix symbol.cpp includes
* Updated formatting target
- include *.cmake files
* Updated causal tests
- causal tests should be stable now
* Update timemory and dyninst submodules
- TPLs are stripped + built w/o debug info
* Increase tolerance for causal validation speedups
- higher speedups have more variance (increased to +/- 5 from 3)
* Support causal output for MPI
- i.e. tag with MPI rank
* omnitrace-causal launcher argument
* improve experiment sampling output
* causal data updates
- call compute lines once
- fixed filtered cached binary info
- debugging info when experiment fails to start
* Tweaked causal validation tests
* dwarf_entry ranges
* CI updates
- increase max threads to 64
* Tweak causal E2E validation tests
- more threads
- shorter thread runtime
- more iterations
* Fix shadowed variable
* fix symbol read_bfd last PC calculation
* fix maybe-uninitialized warning
* omnitrace-causal launcher update
- only inject "omnitrace-causal --" once
- throw error if no matches found
* Update causal profiling docs for launcher
* fix address range boundaries
3.4 KiB
About
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:glob:
:maxdepth: 4
Overview
OmniTrace is an AMD open source research project and is not supported as part of the ROCm software stack.
Browse OmniTrace source code on Github
OmniTrace is designed for both high-level profiling and comprehensive tracing of applications running on the CPU or the CPU+GPU via dynamic binary instrumentation, call-stack sampling, and various other means for determining currently executing function and line information.
Visualization of the comprehensive omnitrace results can be viewed in any modern web browser by visiting
ui.perfetto.dev and loading the perfetto output (.proto files) produced by omnitrace.
Aggregated high-level results are available in text files for human consumption and JSON files for programmatic analysis. The JSON output files are compatible with the python package hatchet which converts the performance data into pandas dataframes and facilitate multi-run comparisons, filtering, visualization in Jupyter notebooks, and much more.
OmniTrace has two distinct configuration steps when instrumenting:
- Configuring which functions and modules are instrumented in the target binaries (i.e. executable and/or libraries)
- Configuring what the instrumentation does happens when the instrumented binaries are executed
OmniTrace Use Cases
When analyzing the performance of an application, it is always best to NOT assume you know where the performance bottlenecks are and why they are happening. OmniTrace is a tool for the entire execution of application. It is the sort of tool which is ideal for characterizing where optimization would have the greatest impact on the end-to-end execution of the application and/or viewing what else is happening on the system during a performance bottleneck.
Especially when GPUs are involved, there is a tendency to assume that the quickest path to performance improvement is minimizing the runtime of the GPU kernels. This is a highly flawed assumption: if you optimize the runtime of a kernel from 1 millisecond to 1 microsecond (1000x speed-up) but the original application never spent time waiting for kernel(s) to complete, you will see zero statistically significant speed-up in end-to-end runtime of your application. In other words, it does not matter how fast or slow the code on GPU is if the application is not bottlenecked waiting on the GPU.
Use OmniTrace to obtain a high-level view of the entire application. Use it to determine where the performance bottlenecks are and obtain clues to why these bottlenecks are happening. If you want extensive insight into the execution of individual kernels on the GPU, AMD Research is working on another tool for this but you should start with the tool which characterizes the broad picture: OmniTrace.
With regard to the CPU, OmniTrace does not target any specific vendor, it works just as well with non-AMD CPUs as with AMD CPUs. With regard to the GPU, OmniTrace is currently restricted to the HIP and HSA APIs and kernels executing on AMD GPUs.