Ever wondered what's making your binary big? Bloaty McBloatface will show you a size profile of the binary so you can understand what's taking up space inside.
Bloaty performs a deep analysis of the binary. Using custom ELF, DWARF, and Mach-O parsers, Bloaty aims to accurately attribute every byte of the binary to the symbol or compileunit that produced it. It will even disassemble the binary looking for references to anonymous data. For more information about the analysis performed by Bloaty, please see doc/how-bloaty-works.md.
Bloaty works on binaries, shared objects, object files, and
static libraries (.a files). The following file formats
are supported:
- ELF
- Mach-O
- WebAssembly (experimental)
These formats are NOT supported, but I am very interested in adding support for them (I may implement these myself but would also be happy to get contributions!)
- PE/COFF (not supported)
- Android APK (not supported, might be tricky due to compression)
This is not an official Google product.
Building Bloaty requires CMake. On Ubuntu, install this with:
$ sudo apt install cmake
and on macOS, this can be installed using homebrew with:
$ brew install cmake
Bloaty bundles libprotobuf, re2, capstone, and pkg-config as Git submodules, and uses protoc build from libprotobuf, but it will prefer the system's versions of those dependencies if available. All other dependencies are included as Git submodules.
If the Git repository hasn't been cloned with the --recursive, the submodules can be checked out with:
$ git submodule update --init --recursive
To build, run:
$ cmake .
$ make -j6
To run tests (Git only, these are not included in the release tarball), type:
$ make test
All the normal CMake features are available, like out-of-source builds:
$ mkdir build
$ cd build
$ cmake ..
$ make -j6
Run it directly on a binary target. For example, run it on itself.
$ ./bloaty bloaty
On Linux you'll see output something like:
$ ./bloaty bloaty
FILE SIZE VM SIZE
-------------- --------------
30.0% 8.85Mi 0.0% 0 .debug_info
24.7% 7.29Mi 0.0% 0 .debug_loc
12.8% 3.79Mi 0.0% 0 .debug_str
9.7% 2.86Mi 42.8% 2.86Mi .rodata
6.9% 2.03Mi 30.3% 2.03Mi .text
6.3% 1.85Mi 0.0% 0 .debug_line
4.0% 1.19Mi 0.0% 0 .debug_ranges
0.0% 0 15.0% 1.01Mi .bss
1.6% 473Ki 0.0% 0 .strtab
1.4% 435Ki 6.3% 435Ki .data
0.8% 254Ki 3.7% 254Ki .eh_frame
0.8% 231Ki 0.0% 0 .symtab
0.5% 142Ki 0.0% 0 .debug_abbrev
0.2% 56.8Ki 0.8% 56.8Ki .gcc_except_table
0.1% 41.4Ki 0.6% 41.4Ki .eh_frame_hdr
0.0% 11.4Ki 0.1% 9.45Ki [26 Others]
0.0% 7.20Ki 0.1% 7.14Ki .dynstr
0.0% 6.09Ki 0.1% 6.02Ki .dynsym
0.0% 4.89Ki 0.1% 4.83Ki .rela.plt
0.0% 4.59Ki 0.0% 0 [Unmapped]
0.0% 3.30Ki 0.0% 3.23Ki .plt
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
The "VM SIZE" column tells you how much space the binary will take when it is loaded into memory. The "FILE SIZE" column tells you about how much space the binary is taking on disk. These two can be very different from each other:
- Some data lives in the file but isn't loaded into memory, like debug information.
- Some data is mapped into memory but doesn't exist in the
file. This mainly applies to the
.bsssection (zero-initialized data).
The default breakdown in Bloaty is by sections, but many other ways of slicing the binary are supported such as symbols and segments. If you compiled with debug info, you can even break down by compile units and inlines!
$ ./bloaty bloaty -d compileunits
FILE SIZE VM SIZE
-------------- --------------
34.8% 10.2Mi 43.4% 2.91Mi [163 Others]
17.2% 5.08Mi 4.3% 295Ki third_party/protobuf/src/google/protobuf/descriptor.cc
7.3% 2.14Mi 2.6% 179Ki third_party/protobuf/src/google/protobuf/descriptor.pb.cc
4.6% 1.36Mi 1.1% 78.4Ki third_party/protobuf/src/google/protobuf/text_format.cc
3.7% 1.10Mi 4.5% 311Ki third_party/capstone/arch/ARM/ARMDisassembler.c
1.3% 399Ki 15.9% 1.07Mi third_party/capstone/arch/M68K/M68KDisassembler.c
3.2% 980Ki 1.1% 75.3Ki third_party/protobuf/src/google/protobuf/generated_message_reflection.cc
3.2% 965Ki 0.6% 40.7Ki third_party/protobuf/src/google/protobuf/descriptor_database.cc
2.8% 854Ki 12.0% 819Ki third_party/capstone/arch/X86/X86Mapping.c
2.8% 846Ki 1.0% 66.4Ki third_party/protobuf/src/google/protobuf/extension_set.cc
2.7% 800Ki 0.6% 41.2Ki third_party/protobuf/src/google/protobuf/generated_message_util.cc
2.3% 709Ki 0.7% 50.7Ki third_party/protobuf/src/google/protobuf/wire_format.cc
2.1% 637Ki 1.7% 117Ki third_party/demumble/third_party/libcxxabi/cxa_demangle.cpp
1.8% 549Ki 1.7% 114Ki src/bloaty.cc
1.7% 503Ki 0.7% 48.1Ki third_party/protobuf/src/google/protobuf/repeated_field.cc
1.6% 469Ki 6.2% 427Ki third_party/capstone/arch/X86/X86DisassemblerDecoder.c
1.4% 434Ki 0.2% 15.9Ki third_party/protobuf/src/google/protobuf/message.cc
1.4% 422Ki 0.3% 23.4Ki third_party/re2/re2/dfa.cc
1.3% 407Ki 0.4% 24.9Ki third_party/re2/re2/regexp.cc
1.3% 407Ki 0.4% 29.9Ki third_party/protobuf/src/google/protobuf/map_field.cc
1.3% 397Ki 0.4% 24.8Ki third_party/re2/re2/re2.cc
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
Run Bloaty with --help to see a list of available options:
$ ./bloaty --help
Bloaty McBloatface: a size profiler for binaries.
USAGE: bloaty [OPTION]... FILE... [-- BASE_FILE...]
Options:
--csv Output in CSV format instead of human-readable.
--tsv Output in TSV format instead of human-readable.
-c FILE Load configuration from <file>.
-d SOURCE,SOURCE Comma-separated list of sources to scan.
--debug-file=FILE Use this file for debug symbols and/or symbol table.
-C MODE How to demangle symbols. Possible values are:
--demangle=MODE --demangle=none no demangling, print raw symbols
--demangle=short demangle, but omit arg/return types
--demangle=full print full demangled type
The default is --demangle=short.
--disassemble=FUNCTION
Disassemble this function (EXPERIMENTAL)
--domain=DOMAIN Which domains to show. Possible values are:
--domain=vm
--domain=file
--domain=both (the default)
-n NUM How many rows to show per level before collapsing
other keys into '[Other]'. Set to '0' for unlimited.
Defaults to 20.
-s SORTBY Whether to sort by VM or File size. Possible values
are:
-s vm
-s file
-s both (the default: sorts by max(vm, file)).
-w Wide output; don't truncate long labels.
--help Display this message and exit.
--list-sources Show a list of available sources and exit.
--source-filter=PATTERN
Only show keys with names matching this pattern.
Options for debugging Bloaty:
--debug-vmaddr=ADDR
--debug-fileoff=OFF
Print extended debugging information for the given
VM address and/or file offset.
-v Verbose output. Dumps warnings encountered during
processing and full VM/file maps at the end.
Add more v's (-vv, -vvv) for even more.
You can use Bloaty to see how the size of a binary changed.
On the command-line, pass -- followed by the files you
want to use as the diff base.
For example, here is a size diff between a couple different versions of Bloaty, showing how it grew when I added some features.
$ ./bloaty bloaty -- oldbloaty
VM SIZE FILE SIZE
-------------- --------------
[ = ] 0 .debug_loc +688Ki +9.9%
+19% +349Ki .text +349Ki +19%
[ = ] 0 .debug_ranges +180Ki +11%
[ = ] 0 .debug_info +120Ki +0.9%
+23% +73.5Ki .rela.dyn +73.5Ki +23%
+3.5% +57.1Ki .rodata +57.1Ki +3.5%
+28e3% +53.9Ki .data +53.9Ki +28e3%
[ = ] 0 .debug_line +40.2Ki +4.8%
+2.3% +5.35Ki .eh_frame +5.35Ki +2.3%
-6.0% -5 [Unmapped] +2.65Ki +215%
+0.5% +1.70Ki .dynstr +1.70Ki +0.5%
[ = ] 0 .symtab +1.59Ki +0.9%
[ = ] 0 .debug_abbrev +1.29Ki +0.5%
[ = ] 0 .strtab +1.26Ki +0.3%
+16% +992 .bss 0 [ = ]
+0.2% +642 [13 Others] +849 +0.2%
+0.6% +792 .dynsym +792 +0.6%
+16% +696 .rela.plt +696 +16%
+16% +464 .plt +464 +16%
+0.8% +312 .eh_frame_hdr +312 +0.8%
[ = ] 0 .debug_str -19.6Ki -0.4%
+11% +544Ki TOTAL +1.52Mi +4.6%
Each line shows the how much each part changed compared to
its previous size. Most sections grew, but one section at
the bottom (.debug_str) shrank. The "TOTAL" line shows
how much the size changed overall.
Bloaty supports breaking the binary down in lots of
different ways. You can combine multiple data sources into
a single hierarchical profile. For example, we can use the
segments and sections data sources in a single report:
$ ./bloaty -d segments,sections bloaty
FILE SIZE VM SIZE
-------------- --------------
80.7% 23.8Mi 0.0% 0 [Unmapped]
37.2% 8.85Mi NAN% 0 .debug_info
30.6% 7.29Mi NAN% 0 .debug_loc
15.9% 3.79Mi NAN% 0 .debug_str
7.8% 1.85Mi NAN% 0 .debug_line
5.0% 1.19Mi NAN% 0 .debug_ranges
1.9% 473Ki NAN% 0 .strtab
1.0% 231Ki NAN% 0 .symtab
0.6% 142Ki NAN% 0 .debug_abbrev
0.0% 4.59Ki NAN% 0 [Unmapped]
0.0% 392 NAN% 0 .shstrtab
0.0% 139 NAN% 0 .debug_macinfo
0.0% 68 NAN% 0 .comment
10.9% 3.21Mi 47.9% 3.21Mi LOAD #4 [R]
89.3% 2.86Mi 89.3% 2.86Mi .rodata
7.7% 254Ki 7.7% 254Ki .eh_frame
1.7% 56.8Ki 1.7% 56.8Ki .gcc_except_table
1.3% 41.4Ki 1.3% 41.4Ki .eh_frame_hdr
0.0% 1 0.0% 1 [LOAD #4 [R]]
6.9% 2.03Mi 30.3% 2.03Mi LOAD #3 [RX]
99.8% 2.03Mi 99.8% 2.03Mi .text
0.2% 3.23Ki 0.2% 3.23Ki .plt
0.0% 28 0.0% 28 [LOAD #3 [RX]]
0.0% 23 0.0% 23 .init
0.0% 9 0.0% 9 .fini
1.5% 439Ki 21.4% 1.44Mi LOAD #5 [RW]
0.0% 0 70.1% 1.01Mi .bss
99.1% 435Ki 29.6% 435Ki .data
0.4% 1.63Ki 0.1% 1.63Ki .got.plt
0.3% 1.46Ki 0.1% 1.46Ki .data.rel.ro
0.1% 560 0.0% 560 .dynamic
0.1% 384 0.0% 376 .init_array
0.0% 32 0.0% 56 [LOAD #5 [RW]]
0.0% 32 0.0% 32 .got
0.0% 16 0.0% 16 .tdata
0.0% 8 0.0% 8 .fini_array
0.0% 0 0.0% 8 .tbss
0.1% 23.3Ki 0.3% 23.3Ki LOAD #2 [R]
30.7% 7.14Ki 30.7% 7.14Ki .dynstr
25.9% 6.02Ki 25.9% 6.02Ki .dynsym
20.8% 4.83Ki 20.8% 4.83Ki .rela.plt
7.7% 1.78Ki 7.7% 1.78Ki .hash
5.0% 1.17Ki 5.0% 1.17Ki .rela.dyn
3.1% 741 3.1% 741 [LOAD #2 [R]]
2.7% 632 2.7% 632 .gnu.hash
2.2% 514 2.2% 514 .gnu.version
1.6% 384 1.6% 384 .gnu.version_r
0.2% 36 0.2% 36 .note.gnu.build-id
0.1% 32 0.1% 32 .note.ABI-tag
0.1% 28 0.1% 28 .interp
0.0% 2.56Ki 0.0% 0 [ELF Headers]
46.3% 1.19Ki NAN% 0 [19 Others]
7.3% 192 NAN% 0 [ELF Headers]
2.4% 64 NAN% 0 .comment
2.4% 64 NAN% 0 .data
2.4% 64 NAN% 0 .data.rel.ro
2.4% 64 NAN% 0 .debug_abbrev
2.4% 64 NAN% 0 .debug_info
2.4% 64 NAN% 0 .debug_line
2.4% 64 NAN% 0 .debug_loc
2.4% 64 NAN% 0 .debug_macinfo
2.4% 64 NAN% 0 .debug_ranges
2.4% 64 NAN% 0 .debug_str
2.4% 64 NAN% 0 .dynamic
2.4% 64 NAN% 0 .dynstr
2.4% 64 NAN% 0 .dynsym
2.4% 64 NAN% 0 .eh_frame
2.4% 64 NAN% 0 .eh_frame_hdr
2.4% 64 NAN% 0 .fini
2.4% 64 NAN% 0 .fini_array
2.4% 64 NAN% 0 .gcc_except_table
2.4% 64 NAN% 0 .gnu.hash
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
Bloaty displays a maximum of 20 lines for each level; other
values are grouped into an [Other] bin. Use -n <num>
to override this setting. If you pass -n 0, all data
will be output without collapsing anything into [Other].
Bloaty supports reading debuginfo/symbols from separate binaries. This lets you profile a stripped binary, even for data sources like "compileunits" or "symbols" that require this extra information.
Bloaty uses build IDs to verify that the binary and the debug file match. Otherwise the results would be nonsense (this kind of mismatch might sound unlikely but it's a very easy mistake to make, and one that I made several times even as Bloaty's author!).
If your binary has a build ID, then using separate debug files is as simple as:
$ cp bloaty bloaty.stripped
$ strip bloaty.stripped
$ ./bloaty -d symbols --debug-file=bloaty bloaty.stripped
Some format-specific notes follow.
For ELF, make sure you are compiling with build IDs enabled.
With gcc this happens automatically, but Clang decided not
to make this the default, since it makes the link
slower.
For Clang add -Wl,--build-id to your link line. (If you
want a slightly faster link and don't care about
reproducibility, you can use -Wl,--build-id=uuid instead).
Bloaty does not currently support the GNU debuglink or
looking up debug files by build ID, which are the methods
GDB uses to find debug
files.
If there are use cases where Bloaty's --debug-file option
won't work, we can reconsider implementing these.
Mach-O files always have build IDs (as far as I can tell), so no special configuration is needed to make sure you get them.
Mach-O puts debug information in separate files which you
can create with dsymutil:
$ dsymutil bloaty
$ strip bloaty (optional)
$ ./bloaty -d symbols --debug-file=bloaty.dSYM/Contents/Resources/DWARF/bloaty bloaty
Any options that you can specify on the command-line, you
can put into a configuration file instead. Then use can use
-c FILE to load those options from the config file. Also,
a few features are only available with configuration files
and cannot be specify on the command-line.
The configuration file is a in Protocol Buffers text format.
The schema is the Options message in
src/bloaty.proto.
The two most useful cases for configuration files are:
-
You have too many input files to put on the command-line. At Google we sometimes run Bloaty over thousands of input files. This can cause the overall command-line to exceed OS limits. With a config file, we can avoid this:
filename: "path/to/long_filename_a.o" filename: "path/to/long_filename_b.o" filename: "path/to/long_filename_c.o" # ...repeat for thousands of files. -
For custom data sources, it can be very useful to put them in a config file, for greater reusability. For example, see the custom data sources defined in custom_sources.bloaty. Also read more about custom data sources below.
Bloaty has many data sources built in. These all provide different ways of looking at the binary. You can also create your own data sources by applying regexes to the built-in data sources (see "Custom Data Sources" below).
While Bloaty works on binaries, shared objects, object
files, and static libraries (.a files), some of the data
sources don't work on object files. This applies especially
to data sources that read debug info.
Segments are what the run-time loader uses to determine what
parts of the binary need to be loaded/mapped into memory.
There are usually just a few segments: one for each set of
mmap() permissions required:
$ ./bloaty -d segments bloaty
FILE SIZE VM SIZE
-------------- --------------
80.7% 23.8Mi 0.0% 0 [Unmapped]
10.9% 3.21Mi 47.9% 3.21Mi LOAD #4 [R]
6.9% 2.03Mi 30.3% 2.03Mi LOAD #3 [RX]
1.5% 439Ki 21.4% 1.44Mi LOAD #5 [RW]
0.1% 23.3Ki 0.3% 23.3Ki LOAD #2 [R]
0.0% 2.56Ki 0.0% 0 [ELF Headers]
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
Here we see one segment mapped [RX] (read/execute) and
one segment mapped [RW] (read/write). A large part of
the binary is not loaded into memory, which we see as
[Unmapped].
Object files and static libraries don't have segments. However we fake it by grouping sections by their flags. This gives us a break-down sort of like real segments.
$ ./bloaty -d segments CMakeFiles/libbloaty.dir/src/bloaty.cc.o
FILE SIZE VM SIZE
-------------- --------------
87.5% 972Ki 0.0% 0 Section []
8.2% 90.9Ki 78.3% 90.9Ki Section [AX]
2.3% 25.2Ki 21.7% 25.2Ki Section [A]
2.0% 22.6Ki 0.0% 0 [ELF Headers]
0.1% 844 0.0% 0 [Unmapped]
0.0% 24 0.1% 72 Section [AW]
100.0% 1.09Mi 100.0% 116Ki TOTAL
Sections give us a bit more granular look into the binary. If we want to find the symbol table, the unwind information, or the debug information, each kind of information lives in its own section. Bloaty's default output is sections.
$ ./bloaty -d sections bloaty
FILE SIZE VM SIZE
-------------- --------------
30.0% 8.85Mi 0.0% 0 .debug_info
24.7% 7.29Mi 0.0% 0 .debug_loc
12.8% 3.79Mi 0.0% 0 .debug_str
9.7% 2.86Mi 42.8% 2.86Mi .rodata
6.9% 2.03Mi 30.3% 2.03Mi .text
6.3% 1.85Mi 0.0% 0 .debug_line
4.0% 1.19Mi 0.0% 0 .debug_ranges
0.0% 0 15.0% 1.01Mi .bss
1.6% 473Ki 0.0% 0 .strtab
1.4% 435Ki 6.3% 435Ki .data
0.8% 254Ki 3.7% 254Ki .eh_frame
0.8% 231Ki 0.0% 0 .symtab
0.5% 142Ki 0.0% 0 .debug_abbrev
0.2% 56.8Ki 0.8% 56.8Ki .gcc_except_table
0.1% 41.4Ki 0.6% 41.4Ki .eh_frame_hdr
0.0% 11.4Ki 0.1% 9.45Ki [26 Others]
0.0% 7.20Ki 0.1% 7.14Ki .dynstr
0.0% 6.09Ki 0.1% 6.02Ki .dynsym
0.0% 4.89Ki 0.1% 4.83Ki .rela.plt
0.0% 4.59Ki 0.0% 0 [Unmapped]
0.0% 3.30Ki 0.0% 3.23Ki .plt
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
Sections are regions of the binary that are the linker
treats as atomic when linking. The linker will never break
apart or rearrange the data within a section. This is why it
is necessary to compile with -ffunction-sections and
-fdata-sections if you want the linker to strip out
individual functions or variables that have no references.
However the linker will often combine many input sections
into a single output section.
Symbols come from the symbol table, and represent individual functions or variables.
$ ./bloaty -d symbols bloaty
FILE SIZE VM SIZE
-------------- --------------
30.0% 8.85Mi 0.0% 0 [section .debug_info]
24.7% 7.29Mi 0.0% 0 [section .debug_loc]
12.8% 3.79Mi 0.0% 0 [section .debug_str]
11.7% 3.44Mi 41.2% 2.76Mi [5895 Others]
6.3% 1.85Mi 0.0% 0 [section .debug_line]
4.9% 1.43Mi 21.4% 1.43Mi insns
4.0% 1.19Mi 0.0% 0 [section .debug_ranges]
0.0% 44 14.9% 1024Ki g_instruction_table
0.8% 255Ki 3.7% 255Ki [section .rodata]
0.8% 240Ki 3.5% 240Ki printAliasInstr
0.6% 175Ki 2.6% 175Ki insn_ops
0.5% 153Ki 2.2% 153Ki ARMInsts
0.5% 142Ki 0.0% 0 [section .debug_abbrev]
0.5% 140Ki 2.0% 140Ki x86DisassemblerTwoByteOpcodes
0.4% 113Ki 1.6% 113Ki insn_name_maps
0.4% 106Ki 1.6% 106Ki printInstruction.OpInfo
0.3% 97.1Ki 1.4% 96.9Ki printInstruction.OpInfo2
0.2% 74.0Ki 1.1% 74.0Ki x86DisassemblerThreeByte38Opcodes
0.2% 71.1Ki 1.0% 70.8Ki printInstruction.AsmStrs
0.2% 61.1Ki 0.9% 60.9Ki DecoderTable32
0.2% 56.8Ki 0.8% 56.8Ki [section .gcc_except_table]
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
You can control how symbols are demangled with the -C MODE
or --demangle=MODE flag. You can also specify the
demangling mode explicitly in the -d switch. We have
three different demangling modes:
-C noneor-d rawsymbols: no, demangling.-C shortor-d shortsymbols: short demangling: return types, template parameters, and function parameter types are omitted. For example:bloaty::dwarf::FormReader<>::GetFunctionForForm<>(). This is the default.-C fullor-d fullsymbols: full demangling.
One very handy thing about -C short (the default) is that
it groups all template instantiations together, regardless
of their parameters. You can use this to determine how much
code size you are paying by doing multiple instantiations of
templates. Try bloaty -d shortsymbols,fullsymbols.
When you pass multiple files to Bloaty, the inputfiles
source will let you break it down by input file:
$ ./bloaty -d inputfiles CMakeFiles/libbloaty.dir/src/*.o
FILE SIZE VM SIZE
-------------- --------------
42.8% 1.09Mi 37.9% 116Ki CMakeFiles/libbloaty.dir/src/bloaty.cc.o
15.7% 407Ki 15.5% 47.6Ki CMakeFiles/libbloaty.dir/src/dwarf.cc.o
10.3% 266Ki 10.4% 31.8Ki CMakeFiles/libbloaty.dir/src/bloaty.pb.cc.o
9.0% 232Ki 9.7% 29.8Ki CMakeFiles/libbloaty.dir/src/elf.cc.o
8.0% 207Ki 8.7% 26.6Ki CMakeFiles/libbloaty.dir/src/macho.cc.o
4.4% 114Ki 4.3% 13.1Ki CMakeFiles/libbloaty.dir/src/webassembly.cc.o
4.0% 103Ki 7.5% 22.9Ki CMakeFiles/libbloaty.dir/src/demangle.cc.o
3.4% 87.0Ki 3.3% 10.2Ki CMakeFiles/libbloaty.dir/src/range_map.cc.o
2.5% 64.3Ki 2.6% 7.94Ki CMakeFiles/libbloaty.dir/src/disassemble.cc.o
100.0% 2.53Mi 100.0% 306Ki TOTAL
When you are running Bloaty on a .a file, the armembers
source will let you break it down by .o file inside the
archive.
$ ./bloaty -d armembers liblibbloaty.a
FILE SIZE VM SIZE
-------------- --------------
28.5% 1.21Mi 23.5% 120Ki cxa_demangle.cpp.o
25.6% 1.09Mi 22.6% 116Ki bloaty.cc.o
9.4% 407Ki 9.3% 47.6Ki dwarf.cc.o
6.2% 266Ki 6.2% 31.8Ki bloaty.pb.cc.o
5.4% 232Ki 5.8% 29.8Ki elf.cc.o
4.8% 207Ki 5.2% 26.6Ki macho.cc.o
2.6% 114Ki 2.6% 13.1Ki webassembly.cc.o
2.4% 103Ki 4.5% 22.9Ki demangle.cc.o
2.0% 87.0Ki 2.0% 10.2Ki range_map.cc.o
1.9% 80.4Ki 3.2% 16.7Ki charconv_bigint.cc.o
1.8% 79.3Ki 2.7% 14.0Ki escaping.cc.o
1.5% 65.0Ki 2.1% 10.9Ki [9 Others]
1.5% 64.3Ki 1.5% 7.94Ki disassemble.cc.o
1.4% 59.9Ki 0.0% 0 [AR Symbol Table]
1.0% 45.2Ki 2.4% 12.4Ki numbers.cc.o
0.9% 40.9Ki 2.2% 11.4Ki charconv.cc.o
0.9% 38.8Ki 1.2% 6.10Ki int128.cc.o
0.7% 30.1Ki 1.1% 5.58Ki str_cat.cc.o
0.6% 24.1Ki 0.8% 3.92Ki string_view.cc.o
0.5% 21.2Ki 0.6% 3.21Ki throw_delegate.cc.o
0.4% 19.2Ki 0.4% 2.26Ki ascii.cc.o
100.0% 4.23Mi 100.0% 512Ki TOTAL
You are free to use this data source even for non-.a
files, but it won't be very useful since it will always just
resolve to the input file (the .a file).
Using debug information, we can tell what compile unit (and corresponding source file) each bit of the binary came from.
$ ./bloaty -d compileunits bloaty
FILE SIZE VM SIZE
-------------- --------------
34.8% 10.2Mi 43.4% 2.91Mi [163 Others]
17.2% 5.08Mi 4.3% 295Ki third_party/protobuf/src/google/protobuf/descriptor.cc
7.3% 2.14Mi 2.6% 179Ki third_party/protobuf/src/google/protobuf/descriptor.pb.cc
4.6% 1.36Mi 1.1% 78.4Ki third_party/protobuf/src/google/protobuf/text_format.cc
3.7% 1.10Mi 4.5% 311Ki third_party/capstone/arch/ARM/ARMDisassembler.c
1.3% 399Ki 15.9% 1.07Mi third_party/capstone/arch/M68K/M68KDisassembler.c
3.2% 980Ki 1.1% 75.3Ki third_party/protobuf/src/google/protobuf/generated_message_reflection.cc
3.2% 965Ki 0.6% 40.7Ki third_party/protobuf/src/google/protobuf/descriptor_database.cc
2.8% 854Ki 12.0% 819Ki third_party/capstone/arch/X86/X86Mapping.c
2.8% 846Ki 1.0% 66.4Ki third_party/protobuf/src/google/protobuf/extension_set.cc
2.7% 800Ki 0.6% 41.2Ki third_party/protobuf/src/google/protobuf/generated_message_util.cc
2.3% 709Ki 0.7% 50.7Ki third_party/protobuf/src/google/protobuf/wire_format.cc
2.1% 637Ki 1.7% 117Ki third_party/demumble/third_party/libcxxabi/cxa_demangle.cpp
1.8% 549Ki 1.7% 114Ki src/bloaty.cc
1.7% 503Ki 0.7% 48.1Ki third_party/protobuf/src/google/protobuf/repeated_field.cc
1.6% 469Ki 6.2% 427Ki third_party/capstone/arch/X86/X86DisassemblerDecoder.c
1.4% 434Ki 0.2% 15.9Ki third_party/protobuf/src/google/protobuf/message.cc
1.4% 422Ki 0.3% 23.4Ki third_party/re2/re2/dfa.cc
1.3% 407Ki 0.4% 24.9Ki third_party/re2/re2/regexp.cc
1.3% 407Ki 0.4% 29.9Ki third_party/protobuf/src/google/protobuf/map_field.cc
1.3% 397Ki 0.4% 24.8Ki third_party/re2/re2/re2.cc
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
The DWARF debugging information also contains "line info" information that understands inlining. So within a function, it will know which instructions came from an inlined function from a header file. This is the information the debugger uses to point at a specific source line as you're tracing through a program.
$ ./bloaty -d inlines bloaty
FILE SIZE VM SIZE
-------------- --------------
30.0% 8.85Mi 0.0% 0 [section .debug_info]
24.7% 7.29Mi 0.0% 0 [section .debug_loc]
12.8% 3.79Mi 0.0% 0 [section .debug_str]
9.7% 2.86Mi 42.8% 2.86Mi [section .rodata]
6.6% 1.96Mi 29.1% 1.95Mi [44060 Others]
6.3% 1.85Mi 0.0% 0 [section .debug_line]
4.0% 1.19Mi 0.0% 0 [section .debug_ranges]
0.0% 0 15.0% 1.01Mi [section .bss]
1.6% 473Ki 0.0% 0 [section .strtab]
1.4% 435Ki 6.3% 435Ki [section .data]
0.8% 254Ki 3.7% 254Ki [section .eh_frame]
0.8% 231Ki 0.0% 0 [section .symtab]
0.5% 142Ki 0.0% 0 [section .debug_abbrev]
0.2% 56.8Ki 0.8% 56.8Ki [section .gcc_except_table]
0.1% 41.4Ki 0.6% 41.4Ki [section .eh_frame_hdr]
0.1% 27.4Ki 0.4% 27.4Ki /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.h:187
0.1% 19.1Ki 0.3% 19.1Ki /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.h:183
0.1% 16.8Ki 0.2% 16.8Ki /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/ext/new_allocator.h:128
0.1% 16.0Ki 0.2% 16.0Ki /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/char_traits.h:300
0.1% 15.8Ki 0.2% 15.8Ki /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.h:222
0.0% 14.7Ki 0.2% 14.7Ki [section .text]
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
Sometimes you want to munge the labels from an existing data source. For example, when we use "compileunits" on Bloaty itself, we see files from all our dependencies mixed together:
$ ./bloaty -d compileunits bloaty
FILE SIZE VM SIZE
-------------- --------------
34.8% 10.2Mi 43.4% 2.91Mi [163 Others]
17.2% 5.08Mi 4.3% 295Ki third_party/protobuf/src/google/protobuf/descriptor.cc
7.3% 2.14Mi 2.6% 179Ki third_party/protobuf/src/google/protobuf/descriptor.pb.cc
4.6% 1.36Mi 1.1% 78.4Ki third_party/protobuf/src/google/protobuf/text_format.cc
3.7% 1.10Mi 4.5% 311Ki third_party/capstone/arch/ARM/ARMDisassembler.c
1.3% 399Ki 15.9% 1.07Mi third_party/capstone/arch/M68K/M68KDisassembler.c
3.2% 980Ki 1.1% 75.3Ki third_party/protobuf/src/google/protobuf/generated_message_reflection.cc
3.2% 965Ki 0.6% 40.7Ki third_party/protobuf/src/google/protobuf/descriptor_database.cc
2.8% 854Ki 12.0% 819Ki third_party/capstone/arch/X86/X86Mapping.c
2.8% 846Ki 1.0% 66.4Ki third_party/protobuf/src/google/protobuf/extension_set.cc
2.7% 800Ki 0.6% 41.2Ki third_party/protobuf/src/google/protobuf/generated_message_util.cc
2.3% 709Ki 0.7% 50.7Ki third_party/protobuf/src/google/protobuf/wire_format.cc
2.1% 637Ki 1.7% 117Ki third_party/demumble/third_party/libcxxabi/cxa_demangle.cpp
1.8% 549Ki 1.7% 114Ki src/bloaty.cc
1.7% 503Ki 0.7% 48.1Ki third_party/protobuf/src/google/protobuf/repeated_field.cc
1.6% 469Ki 6.2% 427Ki third_party/capstone/arch/X86/X86DisassemblerDecoder.c
1.4% 434Ki 0.2% 15.9Ki third_party/protobuf/src/google/protobuf/message.cc
1.4% 422Ki 0.3% 23.4Ki third_party/re2/re2/dfa.cc
1.3% 407Ki 0.4% 24.9Ki third_party/re2/re2/regexp.cc
1.3% 407Ki 0.4% 29.9Ki third_party/protobuf/src/google/protobuf/map_field.cc
1.3% 397Ki 0.4% 24.8Ki third_party/re2/re2/re2.cc
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
If we want to bucket all of these by which library they came from, we can write a custom data source. It specifies the base data source and a set of regexes to apply to it. The regexes are tried in order, and the first matching regex will cause the entire label to be rewritten to the replacement text. Regexes follow RE2 syntax and the replacement can refer to capture groups.
$ cat bloaty_package.bloaty
custom_data_source: {
name: "bloaty_package"
base_data_source: "compileunits"
rewrite: {
pattern: "^(\\.\\./)?src"
replacement: "src"
}
rewrite: {
pattern: "^(\\.\\./)?(third_party/\\w+)"
replacement: "\\2"
}
}
Then use the data source like so:
$ ./bloaty -c bloaty_package.bloaty -d bloaty_package bloaty
FILE SIZE VM SIZE
-------------- --------------
56.6% 16.7Mi 16.6% 1.11Mi third_party/protobuf
24.9% 7.35Mi 68.5% 4.58Mi third_party/capstone
9.4% 2.77Mi 3.2% 221Ki third_party/re2
4.6% 1.36Mi 4.1% 280Ki src
2.1% 637Ki 1.7% 117Ki third_party/demumble
0.7% 209Ki 1.1% 73.8Ki third_party/abseil
0.7% 204Ki 3.0% 204Ki [section .rodata]
0.2% 56.8Ki 0.8% 56.8Ki [section .gcc_except_table]
0.2% 47.7Ki 0.0% 0 [section .debug_str]
0.2% 46.3Ki 0.0% 0 [section .symtab]
0.1% 42.0Ki 0.6% 42.0Ki [section .text]
0.1% 41.4Ki 0.0% 0 [section .debug_loc]
0.1% 29.3Ki 0.0% 0 [section .strtab]
0.0% 12.0Ki 0.2% 11.5Ki [30 Others]
0.0% 7.36Ki 0.0% 0 [section .debug_ranges]
0.0% 6.10Ki 0.1% 6.10Ki [section .dynstr]
0.0% 4.99Ki 0.1% 4.99Ki [section .dynsym]
0.0% 4.77Ki 0.1% 4.77Ki [section .eh_frame]
0.0% 4.59Ki 0.0% 0 [Unmapped]
0.0% 3.23Ki 0.0% 3.23Ki [section .plt]
0.0% 2.50Ki 0.0% 0 [ELF Headers]
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
We can get an even richer report by combining the
bloaty_package source with the original compileunits
source:
$ ./bloaty -c config.bloaty -d bloaty_package,compileunits bloaty
FILE SIZE VM SIZE
-------------- --------------
56.6% 16.7Mi 16.6% 1.11Mi third_party/protobuf
30.5% 5.08Mi 26.0% 295Ki third_party/protobuf/src/google/protobuf/descriptor.cc
12.8% 2.14Mi 15.8% 179Ki third_party/protobuf/src/google/protobuf/descriptor.pb.cc
8.2% 1.36Mi 6.9% 78.4Ki third_party/protobuf/src/google/protobuf/text_format.cc
5.7% 980Ki 6.6% 75.3Ki third_party/protobuf/src/google/protobuf/generated_message_reflection.cc
5.7% 965Ki 3.6% 40.7Ki third_party/protobuf/src/google/protobuf/descriptor_database.cc
5.0% 846Ki 5.8% 66.4Ki third_party/protobuf/src/google/protobuf/extension_set.cc
4.7% 800Ki 3.6% 41.2Ki third_party/protobuf/src/google/protobuf/generated_message_util.cc
4.7% 798Ki 6.1% 69.3Ki [16 Others]
4.2% 709Ki 4.5% 50.7Ki third_party/protobuf/src/google/protobuf/wire_format.cc
2.9% 503Ki 4.2% 48.1Ki third_party/protobuf/src/google/protobuf/repeated_field.cc
2.5% 434Ki 1.4% 15.9Ki third_party/protobuf/src/google/protobuf/message.cc
2.4% 407Ki 2.6% 29.9Ki third_party/protobuf/src/google/protobuf/map_field.cc
1.8% 309Ki 2.4% 27.5Ki third_party/protobuf/src/google/protobuf/stubs/strutil.cc
1.5% 256Ki 0.8% 9.19Ki third_party/protobuf/src/google/protobuf/dynamic_message.cc
1.2% 208Ki 1.2% 13.2Ki third_party/protobuf/src/google/protobuf/extension_set_heavy.cc
1.2% 206Ki 2.4% 27.4Ki third_party/protobuf/src/google/protobuf/wire_format_lite.cc
1.1% 192Ki 1.6% 17.7Ki third_party/protobuf/src/google/protobuf/parse_context.cc
1.1% 187Ki 0.8% 9.33Ki third_party/protobuf/src/google/protobuf/reflection_ops.cc
1.0% 167Ki 1.2% 13.9Ki third_party/protobuf/src/google/protobuf/message_lite.cc
1.0% 165Ki 1.6% 18.7Ki third_party/protobuf/src/google/protobuf/io/tokenizer.cc
0.9% 152Ki 0.7% 7.57Ki third_party/protobuf/src/google/protobuf/unknown_field_set.cc
24.9% 7.35Mi 68.5% 4.58Mi third_party/capstone
17.4% 1.28Mi 6.5% 303Ki [38 Others]
14.9% 1.10Mi 6.6% 311Ki third_party/capstone/arch/ARM/ARMDisassembler.c
5.3% 399Ki 23.3% 1.07Mi third_party/capstone/arch/M68K/M68KDisassembler.c
11.4% 854Ki 17.5% 819Ki third_party/capstone/arch/X86/X86Mapping.c
6.2% 469Ki 9.1% 427Ki third_party/capstone/arch/X86/X86DisassemblerDecoder.c
4.8% 363Ki 1.3% 59.1Ki third_party/capstone/arch/SystemZ/SystemZDisassembler.c
4.4% 329Ki 1.2% 54.2Ki third_party/capstone/arch/Mips/MipsDisassembler.c
4.2% 314Ki 1.6% 73.0Ki third_party/capstone/arch/AArch64/AArch64Disassembler.c
3.4% 256Ki 3.1% 145Ki third_party/capstone/arch/AArch64/AArch64InstPrinter.c
3.2% 243Ki 4.7% 219Ki third_party/capstone/arch/AArch64/AArch64Mapping.c
3.2% 241Ki 4.7% 220Ki third_party/capstone/arch/SystemZ/SystemZMapping.c
2.9% 219Ki 4.2% 196Ki third_party/capstone/arch/ARM/ARMMapping.c
2.7% 205Ki 1.8% 83.3Ki third_party/capstone/arch/ARM/ARMInstPrinter.c
2.2% 166Ki 2.0% 95.4Ki third_party/capstone/arch/PowerPC/PPCInstPrinter.c
2.0% 153Ki 2.8% 132Ki third_party/capstone/arch/Mips/MipsMapping.c
2.0% 153Ki 0.4% 17.7Ki third_party/capstone/arch/TMS320C64x/TMS320C64xDisassembler.c
2.0% 151Ki 2.1% 99.0Ki third_party/capstone/arch/X86/X86ATTInstPrinter.c
2.0% 149Ki 1.9% 90.6Ki third_party/capstone/arch/Sparc/SparcInstPrinter.c
2.0% 148Ki 2.7% 126Ki third_party/capstone/arch/PowerPC/PPCMapping.c
1.9% 146Ki 2.1% 96.2Ki third_party/capstone/arch/X86/X86IntelInstPrinter.c
1.7% 124Ki 0.6% 28.7Ki third_party/capstone/arch/PowerPC/PPCDisassembler.c
9.4% 2.77Mi 3.2% 221Ki third_party/re2
14.9% 422Ki 10.6% 23.4Ki third_party/re2/re2/dfa.cc
14.4% 407Ki 11.3% 24.9Ki third_party/re2/re2/regexp.cc
14.0% 397Ki 11.2% 24.8Ki third_party/re2/re2/re2.cc
12.2% 345Ki 10.0% 22.1Ki third_party/re2/re2/prog.cc
11.4% 322Ki 33.1% 73.2Ki third_party/re2/re2/parse.cc
10.3% 292Ki 8.9% 19.6Ki third_party/re2/re2/compile.cc
5.6% 159Ki 3.7% 8.08Ki third_party/re2/re2/nfa.cc
4.6% 130Ki 4.7% 10.5Ki third_party/re2/re2/simplify.cc
3.7% 106Ki 1.9% 4.19Ki third_party/re2/re2/onepass.cc
3.1% 88.7Ki 1.4% 3.08Ki third_party/re2/re2/bitstate.cc
2.9% 83.6Ki 1.6% 3.50Ki third_party/re2/re2/tostring.cc
1.1% 31.3Ki 0.6% 1.41Ki third_party/re2/re2/stringpiece.cc
0.9% 24.3Ki 0.6% 1.22Ki third_party/re2/util/strutil.cc
0.6% 16.2Ki 0.0% 0 third_party/re2/re2/unicode_groups.cc
0.2% 5.36Ki 0.5% 1.09Ki third_party/re2/util/rune.cc
0.1% 1.50Ki 0.0% 0 third_party/re2/re2/perl_groups.cc
0.0% 661 0.0% 0 third_party/re2/re2/unicode_casefold.cc
4.6% 1.36Mi 4.1% 280Ki src
39.4% 549Ki 40.7% 114Ki src/bloaty.cc
13.9% 193Ki 15.0% 42.1Ki src/dwarf.cc
10.8% 150Ki 0.5% 1.28Ki src/main.cc
8.1% 113Ki 8.9% 25.0Ki src/bloaty.pb.cc
7.7% 108Ki 9.0% 25.2Ki src/elf.cc
7.2% 99.9Ki 10.3% 29.0Ki src/macho.cc
4.7% 66.2Ki 7.0% 19.5Ki src/demangle.cc
3.5% 49.5Ki 3.8% 10.5Ki src/webassembly.cc
2.8% 38.8Ki 2.7% 7.50Ki src/range_map.cc
1.9% 26.2Ki 2.1% 5.98Ki src/disassemble.cc
2.1% 637Ki 1.7% 117Ki third_party/demumble
100.0% 637Ki 100.0% 117Ki third_party/demumble/third_party/libcxxabi/cxa_demangle.cpp
0.7% 209Ki 1.1% 73.8Ki third_party/abseil
19.0% 39.8Ki 19.0% 14.0Ki third_party/abseil-cpp/absl/strings/internal/charconv_bigint.cc
15.6% 32.6Ki 13.6% 10.1Ki third_party/abseil-cpp/absl/strings/escaping.cc
14.9% 31.1Ki 25.0% 18.5Ki third_party/abseil-cpp/absl/strings/charconv.cc
12.3% 25.7Ki 10.6% 7.79Ki third_party/abseil-cpp/absl/numeric/int128.cc
8.5% 17.9Ki 9.0% 6.65Ki third_party/abseil-cpp/absl/strings/numbers.cc
6.8% 14.3Ki 5.2% 3.87Ki third_party/abseil-cpp/absl/strings/str_cat.cc
6.1% 12.7Ki 5.1% 3.75Ki third_party/abseil-cpp/absl/strings/string_view.cc
3.6% 7.49Ki 1.7% 1.23Ki third_party/abseil-cpp/absl/strings/ascii.cc
2.9% 6.10Ki 3.5% 2.56Ki third_party/abseil-cpp/absl/strings/internal/charconv_parse.cc
2.7% 5.75Ki 1.5% 1.13Ki third_party/abseil-cpp/absl/strings/str_split.cc
2.3% 4.84Ki 1.9% 1.40Ki third_party/abseil-cpp/absl/strings/substitute.cc
1.4% 3.03Ki 1.0% 754 third_party/abseil-cpp/absl/base/internal/raw_logging.cc
1.1% 2.28Ki 0.4% 302 third_party/abseil-cpp/absl/base/internal/throw_delegate.cc
0.9% 1.97Ki 1.0% 788 third_party/abseil-cpp/absl/strings/internal/memutil.cc
0.9% 1.93Ki 0.9% 701 third_party/abseil-cpp/absl/strings/internal/escaping.cc
0.7% 1.41Ki 0.4% 293 third_party/abseil-cpp/absl/strings/match.cc
0.3% 556 0.2% 161 third_party/abseil-cpp/absl/strings/internal/utf8.cc
0.7% 204Ki 3.0% 204Ki [section .rodata]
0.2% 56.8Ki 0.8% 56.8Ki [section .gcc_except_table]
0.2% 47.7Ki 0.0% 0 [section .debug_str]
0.2% 46.3Ki 0.0% 0 [section .symtab]
0.1% 42.0Ki 0.6% 42.0Ki [section .text]
0.1% 41.4Ki 0.0% 0 [section .debug_loc]
0.1% 29.3Ki 0.0% 0 [section .strtab]
0.0% 12.0Ki 0.2% 11.5Ki [30 Others]
0.0% 7.36Ki 0.0% 0 [section .debug_ranges]
0.0% 6.10Ki 0.1% 6.10Ki [section .dynstr]
0.0% 4.99Ki 0.1% 4.99Ki [section .dynsym]
0.0% 4.77Ki 0.1% 4.77Ki [section .eh_frame]
0.0% 4.59Ki 0.0% 0 [Unmapped]
0.0% 3.23Ki 0.0% 3.23Ki [section .plt]
0.0% 2.50Ki 0.0% 0 [ELF Headers]
100.0% 29.5Mi 100.0% 6.69Mi TOTAL
Sometimes, you are only interested in parts of the binary instead of the whole package. This is common in embedded programming, where ELF files are used only as a container format, and only a few sections are actually loaded onto the device.
For this, Bloaty provides a --source-filter option which
allows filtering out irrelevant data. It takes a regex
which is applied to each of the symbol names in a data
source. Only symbols which match the regex are displayed
in the output. This is especially powerful when combined
with custom data sources, as the rewriting occurs before
the filtering.
In the case of hierarchical data source profiles, the regex is applied to all symbol names in the hierarchy. If any name matches, all of its parents will be displayed as well.
For example, given the above scenario, maybe we are only
interested in how large the first-party Bloaty code is.
This can be displayed using a source filter on the src
directory.
$ ./bloaty -c config.bloaty -d bloaty_package,compileunits --source-filter ^src bloaty
FILE SIZE VM SIZE
-------------- --------------
100.0% 1.36Mi 100.0% 280Ki src
39.4% 549Ki 40.7% 114Ki src/bloaty.cc
13.9% 193Ki 15.0% 42.1Ki src/dwarf.cc
10.8% 150Ki 0.5% 1.28Ki src/main.cc
8.1% 113Ki 8.9% 25.0Ki src/bloaty.pb.cc
7.7% 108Ki 9.0% 25.2Ki src/elf.cc
7.2% 99.9Ki 10.3% 29.0Ki src/macho.cc
4.7% 66.2Ki 7.0% 19.5Ki src/demangle.cc
3.5% 49.5Ki 3.8% 10.5Ki src/webassembly.cc
2.8% 38.8Ki 2.7% 7.50Ki src/range_map.cc
1.9% 26.2Ki 2.1% 5.98Ki src/disassemble.cc
100.0% 1.36Mi 100.0% 280Ki TOTAL
Filtering enabled (source_filter); omitted file = 28.1Mi, vm = 6.42Mi of entries
Here are some tentative plans for future features.
If we can analyze references between symbols, this would enable a lot of features:
- Detect garbage symbols (ie. how much would the binary
shrink if we compiled with
-ffunction-sections -fdata-sections -Wl,-gc-sections). - Understand why a particular symbol can't be
garbage-collected (like
ld -why_liveon OS X). - Visualize the dependency tree of symbols (probably as a dominator tree) so users can see the weight of their binary in this way.