This is the rebase to the tip of Arnaldo's perf/core repository.
The patch set implements runtime trace compression for record mode and trace file decompression for report mode. Zstandard API [1] is used for compression/decompression of data that come from perf_events kernel data buffers. Realized -z,--compression_level=n option provides ~3-5x avg. trace file size reduction on variety of tested workloads what saves user storage space on larger server systems where trace file size can easily reach several tens or even hundreds of GiBs, especially when profiling with dwarf-based stacks and tracing of context-switches. --mmap-flush option can be used to avoid compressing every single byte of data and increase compression ratio at the same time lowering tool runtime overhead. $ tools/perf/perf record -z 1 -e cycles -- matrix.gcc $ tools/perf/perf record -z 1 --mmap-flush 1024 -e cycles -- matrix.gcc $ tools/perf/perf record -z 1 --mmap-flush 1024 --aio -e cycles -- matrix.gcc The compression functionality can be disabled from the command line using NO_LIBZSTD define and Zstandard sources can be overridden using value of LIBZSTD_DIR define: $ make -C tools/perf NO_LIBZSTD=1 clean all $ make -C tools/perf LIBZSTD_DIR=/path/to/zstd-1.3.7 clean all --- Alexey Budankov (4): feature: realize libzstd check, LIBZSTD_DIR and NO_LIBZSTD defines perf record: implement -z=<level> and --mmap-flush=<thres> options perf record: enable runtime trace compression perf report: support record trace file decompression tools/build/Makefile.feature | 6 +- tools/build/feature/Makefile | 6 +- tools/build/feature/test-all.c | 5 + tools/build/feature/test-libzstd.c | 12 + tools/perf/Documentation/perf-record.txt | 9 + tools/perf/Makefile.config | 20 ++ tools/perf/Makefile.perf | 3 + tools/perf/builtin-record.c | 167 +++++++++++--- tools/perf/builtin-report.c | 5 +- tools/perf/perf.h | 2 + tools/perf/util/env.h | 10 + tools/perf/util/event.c | 1 + tools/perf/util/event.h | 7 + tools/perf/util/evlist.c | 6 +- tools/perf/util/evlist.h | 3 +- tools/perf/util/header.c | 45 +++- tools/perf/util/header.h | 1 + tools/perf/util/mmap.c | 265 +++++++++++++--------- tools/perf/util/mmap.h | 31 ++- tools/perf/util/session.c | 271 ++++++++++++++++++++++- tools/perf/util/session.h | 26 +++ tools/perf/util/tool.h | 2 + 22 files changed, 742 insertions(+), 161 deletions(-) create mode 100644 tools/build/feature/test-libzstd.c --- Changes in v2: - moved compression/decompression code to session layer - enabled allocation aio data buffers for compression - enabled trace compression for serial trace streaming --- [1] https://github.com/facebook/zstd
