v0.12.2

• Metric Functions: Metrics now support built-in functions such as ratio(A, B) and sum(A, B, C, ...), enabling more expressive and reusable formulas (see the documentation).
• Optimized Compile-time Event Injection: The generated runtime event registration class is now only created if it does not already exist, reducing unnecessary recompilation.
• Improved Live Event Accuracy: Live event values now account for partial runtime durations via time scaling, improving accuracy when counters were not active for the full measurement window.

v0.12.1

• Automatic Event Discovery on ARM: Hardware event types are now automatically detected on ARM architectures when initializing a perf::CounterDefinition instance.
• Hardware Counter Introspection: The number of available physical performance counters per logical core, along with the number of events each counter can multiplex, is now determined automatically when creating a perf::EventCounter.
• Recursive and Scientific Metrics: Metric expressions can now reference other metrics recursively. Support for scientific notation (e.g., 1e5) in formula-based metrics has also been added.

v0.12.0

This release expands symbolic analysis capabilities, introduces FlameGraph generation, and improves hardware event management through both runtime and compile-time support.

• Symbol Resolution: Instruction pointers captured during sampling can now be resolved to function names using perf::SymbolResolver (see the documentation).
• FlameGraph Export: Sampling data can be converted into formats compatible with visualization tools such as Brendan Gregg's FlameGraph, Speedscope, and flamegraph.com using perf::analyzer::FlameGraphGenerator (see the documentation).
• Built-in Event Definitions: A set of x86-specific hardware events is now bundled in events/x86 and can be loaded at runtime using perf::CounterDefinition. This serves as an alternative to the make perf-list target.
• Compile-time Event Injection: Processor-specific event definitions can now be embedded directly at build time by configuring CMake with -DGEN_PROCESSOR_EVENTS=1. These are immediately available via perf::CounterDefinition (see the documentation).
• Automatic Event Discovery: Additional event types–including RAPL energy counters and AMD IO MMU events–are now automatically detected during the creation of a perf::CounterDefinition instance (issue #6).

v0.11.1

• Unified the behaviour of the time and timestamp fields in the sampling API, removing discrepancies between the two.

v0.11.0

This version rolls out a redesigned sampling API.
Recorded data are now grouped into dedicated sub-structures (such as Metadata, InstructionExecution, and DataAccess) inside perf::Sample (see the sampling documentation).

The previous flat API is still available but deprecated and will be removed in v0.12.

• New Sampling Interface: Work with clearly separated sample sections, exposing additional AMD IBS fields that are not surfaced by the perf_event_open records.
• Explicit Latency Attributes: Vendor-specific latency signals–cache-access on Intel and cache-miss on AMD–are now surfaced as distinct fields.
• Heterogeneous-core Support: Sampling can target multiple PMU domains (e.g., cpu_core and cpu_atom) on hybrid Intel processors.

v0.10.0

• New feature: The auxiliary event is added automatically if required by the (Intel-) hardware (see the documentation).
• New feature: The Memory Access Analyzer allows the description of complex data objects and maps sampled memory addresses in order to report latency and access information (see the documentation).
• The number of pages for the sampling buffer is now aligned automatically if the number is not configured properly, i.e., a power of two plus one page for the header.
• New feature: Copy sampled data from the mmap-ed perf buffer into the application-level buffer whenever the buffer comes close to full (see the documentation).

v0.9.0

• Removed deprecated warnings about the sampling interface (and the old sampling interface).
• New feature: Access interim results from counters without stopping the counter using live counters.
• New feature: Sampling the user stack.
• New feature: Create custom metrics using expressions, e.g., "instructions/cycles".
• New feature: Use metrics when sampling counter values.
• New feature: Control scheduling of events to physical hardware counters.
• New feature: Added time events (e.g., seconds, milliseconds, etc.) as virtual counters.

v0.8.3

• Fixed multiple compatibility issues, where the code relied on Linux kernel features that might not be available on different versions.

v0.8.2

• Fixed compatibility for older Linux versions that don't provide PERF_MEM_BLK, PERF_MEM_LVLNUM, and PERF_MEM_REMOTE.
• Fixed compatibility for GCC <11 and clang <12.

v0.8.1

• Fixed error using decltype instead of typeof (by @toge )