all: increased toolchain binary sizes

[cagedmantis]

Compared to 1.23, binary sizes of most toolchain binaries have increased :

linux	amd64
Files	Go1.23 (B)	Tip (B)	% (+/-)		Go1.23 (M)	Tip (M)
go	13387863	19362295	+45		12.76	18.46
gofmt	2850696	4108237	+44		2.71	3.91
addr2line	2814484	4547767	+62		2.68	4.3
asm	4106917	6335065	+54		3.91	6.04
buildid	2271515	3656700	+61		2.16	3.48
cgo	4032102	6009954	+49		3.84	5.73
compile	19798633	28201144	+42		18.88	26.89
covdata	2949306	4191031	+42		2.81	3.99
cover	4567071	6723952	+47		4.35	6.41
dist	2984094	4261242	+43		2.84	4.06
distpack	2397807	3743405	+56		2.28	3.56
doc	3392398	4821225	+42		3.23	4.59
fix	2861911	4154515	+45		2.72	3.96
link	5678421	8691638	+53		5.41	8.28
nm	2776817	4490895	+62		2.64	4.28
objdump	3826204	6053727	+58		3.64	5.77
pack	2030214	2982774	+47		1.93	2.84
pprof	12382808	18451654	+49		11.80	17.59
preprofile	2127222	3140546	+48		2.02	2.99
test2json	2295467	3392933	+48		2.18	3.23
trace	12606079	17061695	+35		12.02	16.27
vet	7194248	10024784	+39		6.86	9.56

[gabyhelp]

Related Issues

• all: increased toolchain binary sizes #68109 (closed)
• all: understand binary size changes vs 1.14 #38694
• all: binary size regression #67588 (closed)

Related Code Changes

• cmd/compile,link: use "go.." for compiler genereated types
• cmd/compile: first cut at exporting position info

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[mknyszek]

Those seem fairly large. I preemptively marked this as a release blocker, but maybe OK after RC1. Thoughts?

[mknyszek]

CC @golang/compiler

[cespare]

Is this something about toolchain binaries in particular? I checked a few binaries in our private codebase (all in the 30-60 MB range) and they only get a bit larger between 1.23 and tip (<2%).

[randall77]

There isn't much more code.
objdump -d on arm64 says there are only 3% more instructions in cmd/go on tip than 1.23.

[randall77]

Looks like dwarf, 1.23.2 binaries have their dwarf stripped, tip binaries do not.

I thought we stripped toolchain binaries. Maybe only for release?

[cherrymui]

Yeah, we strip toolchain binaries for releases https://cs.opensource.google/go/go/+/master:src/cmd/dist/build.go;l=1393

[cagedmantis]

These numbers look much better after using distpack (the proper flags). I will update the numbers and remove the release blocker label.

[timothy-king]

Locally I see the following for gofmt:

% objdump -h /Users/taking/sdk/go1.23.1/bin/gofmt                       

/Users/taking/sdk/go1.23.1/bin/gofmt:   file format mach-o arm64

Sections:
Idx Name            Size     VMA              Type
  0 __text          001209c4 0000000100001000 TEXT
  1 __symbol_stub1  0000030c 00000001001219e0 TEXT
  2 __rodata        00038fee 0000000100121d00 DATA
  3 __rodata        0003e800 000000010015c000 DATA
  4 __typelink      00000c34 000000010019a800 DATA
  5 __itablink      00000548 000000010019b440 DATA
  6 __gosymtab      00000000 000000010019b988 DATA
  7 __gopclntab     000bff10 000000010019b9a0 DATA
  8 __go_buildinfo  00000220 000000010025c000 DATA
  9 __nl_symbol_ptr 00000210 000000010025c220 DATA
 10 __noptrdata     0000b360 000000010025c440 DATA
 11 __data          00006c30 00000001002677a0 DATA
 12 __bss           00026760 000000010026e3e0 BSS
 13 __noptrbss      000035a0 0000000100294b40 BSS
% objdump -h /Users/taking/sdk/gotip/bin/gofmt                             

/Users/taking/sdk/gotip/bin/gofmt:      file format mach-o arm64

Sections:
Idx Name             Size     VMA              Type
  0 __text           0011fd44 0000000100001000 TEXT
  1 __symbol_stub1   00000318 0000000100120d60 TEXT
  2 __rodata         0003ac60 0000000100121080 DATA
  3 __rodata         00042d40 000000010015c000 DATA
  4 __typelink       00000cdc 000000010019ed40 DATA
  5 __itablink       00000550 000000010019fa20 DATA
  6 __gosymtab       00000000 000000010019ff70 DATA
  7 __gopclntab      000c6ca0 000000010019ff80 DATA
  8 __go_buildinfo   00000100 0000000100268000 DATA
  9 __go_fipsinfo    00000078 0000000100268100 DATA
 10 __nl_symbol_ptr  00000218 0000000100268178 DATA
 11 __noptrdata      0000ab82 00000001002683a0 DATA
 12 __data           00006db2 0000000100272f40 DATA
 13 __bss            00026890 0000000100279d00 BSS
 14 __noptrbss       00003580 00000001002a05a0 BSS
 15 __zdebug_abbrev  0000014a 00000001002a4000 DATA, DEBUG
 16 __zdebug_line    00036890 00000001002a414a DATA, DEBUG
 17 __zdebug_frame   0000ba53 00000001002da9da DATA, DEBUG
 18 __debug_gdb_scri 00000034 00000001002e642d DATA, DEBUG
 19 __zdebug_info    0006f772 00000001002e6461 DATA, DEBUG
 20 __zdebug_loc     0003ff6c 0000000100355bd3 DATA, DEBUG
 21 __zdebug_ranges  000130f5 0000000100395b3f DATA, DEBUG

The difference in the binary sizes is 1128962 (locally). The extra sections in the gotip copy of gofmt that are not in 1.23.1 copy add up to 1068084 bytes (95%).

[cagedmantis]

The release binaries look much better in terms of the size increase (built with make.bash -distpack):

linux	amd64
files	Go1.23 (bytes)	Tip (bytes)	% (+/-)		MB	MB
go	13387863	14271934	7		12.76766109	13.6107769
gofmt	2850696	2922116	3		2.718635559	2.786746979
addr2line	2814484	3365550	20		2.684101105	3.209638596
asm	4106917	4675184	14		3.916661263	4.458602905
buildid	2271515	2591643	14		2.166285515	2.471583366
cgo	4032102	4365513	8		3.845312119	4.163277626
compile	19798633	20899679	6		18.88144779	19.93148708
covdata	2949306	2999246	2		2.812677383	2.860303879
cover	4567071	4947863	8		4.355498314	4.718649864
dist	2984094	3051249	2		2.845853806	2.909897804
distpack	2397807	2663964	11		2.286726952	2.540554047
doc	3392398	3453200	2		3.235242844	3.293228149
fix	2861911	2959114	3		2.729331017	2.822031021
link	5678421	6242053	10		5.415364265	5.952885628
nm	2776817	3332582	20		2.648179054	3.178197861
objdump	3826204	4621606	21		3.648952484	4.407506943
pack	2030214	2092973	3		1.936162949	1.996014595
pprof	12382808	13910725	12		11.80916595	13.26630116
preprofile	2127222	2208161	4		2.028676987	2.105866432
test2json	2295467	2393740	4		2.189127922	2.282848358
trace	12606079	13407966	6		12.02209377	12.78683281
vet	7194248	7469567	4		6.860969543	7.123534203

[cherrymui]

Thanks @cagedmantis .

objdump's increase is somewhat reasonable, as we added more disassembler support (e.g. s390x disassembler). pprof supports disassembling, so it is probably also reasonable.

The disassembler symbols (golang.org/x/arch stuff) also show up in nm and addr2line, causing them to increase as well. In theory I don't think they need disassembler symbols, so this is unfortunate. I'll see if we can remove those symbols from nm and addr2line.

[andig]

fwiw, I've found that evcc Linux binary slightly shrinks from 1.23 to tip: 91485682 vs 90495826 bytes.

[gopherbot]

Change https://go.dev/cl/634916 mentions this issue: cmd/internal/objfile: break out dissassemblers to another package

[cherrymui]

After nm, addr2line, objdump, and pprof, the next ones are asm and buildid.

One part that they depend on now but not in Go 1.23 is crypto FIPS stuff, as they perform various crypto hash operations. In 1.23 most of the hash operations use notsha256, which is deleted in CL 610599 and switched to real sha256, which now depends on FIPS things. We get some binary size back if we revert back to notsha256. Not completely, though.

Another place for at least cmd/asm is that they now contain a number of different instantiations of slices.Sort routines. The old code was using sort.Sort or sort.Slice, which is not generic. I guess this increase is okay...

[Zxilly]

The tool I wrote includes a diff go binary feature that might come in handy.

https://github.com/Zxilly/go-size-analyzer?tab=readme-ov-file#diff-mode

[cherrymui]

I did another run with GOOS=linux GOARCH=amd64 make.bash -distpack

                  go1.23.3             tip           delta      %delta
          go	  13397287	  14280843	    883556	6.60
       gofmt	   2855408	   2922116	     66708	2.34
   addr2line	   2819123	   2627110	   -192013	-6.81
         asm	   4115652	   4675046	    559394	13.59
     buildid	   2280250	   2591505	    311255	13.65
         cgo	   4040817	   4365375	    324558	8.03
     compile	  19803234	  20934109	   1130875	5.71
     covdata	   2953945	   2999246	     45301	1.53
       cover	   4575841	   4943679	    367838	8.04
         doc	   3401113	   3453200	     52087	1.53
         fix	   2866530	   2959114	     92584	3.23
        link	   5683028	   6246132	    563104	9.91
          nm	   2781456	   2608126	   -173330	-6.23
     objdump	   3830843	   4621684	    790841	20.64
        pack	   2030757	   2092973	     62216	3.06
       pprof	  12387591	  13915107	   1527516	12.33
  preprofile	   2127765	   2208161	     80396	3.78
   test2json	   2300013	   2393740	     93727	4.08
       trace	  12610862	  13412106	    801244	6.35
         vet	   7194840	   7469230	    274390	3.81
----------------------------------------------------------------------
       total	 114056355	 121718602	   7662247	6.72

The changes we inspected are all more or less expected (supporting more features, reasonable refactoring, etc.). I don't think we need to do anything more on this at the moment. Thanks.