A new PoC implementation, adding a compression to trace file. A basic infrastructure for compression support is added into the trace-cmd library. The zlib is used for compression, but more libraries and algorithms can be added. Trace data is commpressed and part of the trace file metadata: - ftrace events format - format of recorded events - information about the mapping of function addresses to the function names - trace_printk() format strings - information of the mapping a PID to a process name - options Note: not all trace-cmd commands are tested with these changes. These are verified to work with compressed trace files: trace-cmd record trace-cmd report trace-cmd dump trace-cmd agent trace-cmd profile trace-cmd split Todo list, in order to have complete trace file compression: - Add support for more compression libraries. - Add new trace-cmd command to convert trace files from version 6 to version 7 and vise versa. - Test all trace-cmd commands with trace file v7. - Update trace-cmd documentation. v4 changes: - Tested and fixed profile and split subcommands with compression files. - Bug fixes. v3 changes: - Compress the trace data. - Added documentation to all compression APIs. - A few minor fixes. v2 changes: - Refactored compression APIs. - Moved the trace buffers description out of the trace options section. - Added compression of "options" section of the trace file. - Updated "trace-cmd list" to show available compression algorithms. - Tested with host-guest tracing. - Merged with the patchset that bumps the trace file version. Tzvetomir Stoyanov (VMware) (29): trace-cmd library: Remove unused private APIs for creating trace files trace-cmd library: Remove unused API tracecmd_update_option trace-cmd: Check if file version is supported trace-cmd library: Add new API to get file version of input handler trace-cmd library: Select the file version when writing trace file trace-cmd: Add APIs for library initialization and free trace-cmd library: Add support for compression algorithms trace-cmd list: Show supported compression algorithms trace-cmd library: Bump the trace file version to 7 trace-cmd library: Compress part of the trace file trace-cmd library: Read compressed trace file trace-cmd library: Add new API to get compression of input handler trace-cmd library: Inherit compression algorithm from input file trace-cmd library: Extend the create file APIs to support different compression trace-cmd record: Add new parameter --compression trace-cmd dump: Add support for trace files version 7 trace-cmd library: Add support for zlib compression library trace-cmd library: Hide the logic for updating buffer offset trace-cmd: Move buffers description outside of options trace-cmd library: Track the offset in the option section in the trace file trace-cmd library: Add compression of the option section of the trace file trace-cmd library: Refactor the logic for writing trace data in the file trace-cmd library: Add APIs for read and write compressed data in chunks trace-cmd: Compress trace data trace-cmd: Read compressed trace data trace-cmd library: Reuse within the library the function that checks file state. trace-cmd library: New internal API to set file state of output handler trace-cmd library: Make tracecmd_copy_headers() to work with output handler trace-cmd: Do not use trace file compression with streams lib/trace-cmd/Makefile | 11 + .../include/private/trace-cmd-private.h | 79 +- lib/trace-cmd/include/trace-cmd-local.h | 25 +- lib/trace-cmd/trace-compress-zlib.c | 172 ++++ lib/trace-cmd/trace-compress.c | 787 ++++++++++++++++++ lib/trace-cmd/trace-input.c | 711 +++++++++++----- lib/trace-cmd/trace-output.c | 738 ++++++++++------ lib/trace-cmd/trace-util.c | 60 ++ tracecmd/trace-cmd.c | 11 +- tracecmd/trace-dump.c | 162 +++- tracecmd/trace-list.c | 26 + tracecmd/trace-listen.c | 3 + tracecmd/trace-read.c | 8 + tracecmd/trace-record.c | 42 +- tracecmd/trace-restore.c | 4 +- tracecmd/trace-stream.c | 2 +- tracecmd/trace-usage.c | 6 + 17 files changed, 2342 insertions(+), 505 deletions(-) create mode 100644 lib/trace-cmd/trace-compress-zlib.c create mode 100644 lib/trace-cmd/trace-compress.c -- 2.31.1