Package libcpucycles: Information

libcpucycles is a public-domain microlibrary for counting CPU
cycles. Cycle counts are not as detailed as Falk diagrams but are the
most precise timers available to typical software; they are central
tools used in understanding and improving software performance.

The libcpucycles API is simple: include <cpucycles.h>, call cpucycles()
to receive a long long whenever desired, and link with -lcpucycles.

Internally, libcpucycles understands machine-level cycle counters for
amd64 (both PMC and TSC), arm32, arm64 (both PMC and VCT), mips64,
ppc32, ppc64, riscv32, riscv64, sparc64, and x86. libcpucycles also
understands four OS-level mechanisms, which give varying levels of
accuracy: mach_absolute_time, perf_event, CLOCK_MONOTONIC, and, as a
fallback, microsecond-resolution gettimeofday.

When the program first calls cpucycles(), libcpucycles automatically
benchmarks the available mechanisms and selects the mechanism that
does the best job. Subsequent cpucycles() calls are thread-safe and
very fast. An accompanying cpucycles-info program prints a summary of
cycle-counter accuracy.

Package libcpucycles: Information

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