Subject: [bug#37305] Making system installation tests faster

From: Maxim Cournoyer <[email-masked]>
Date: Tue, 18 Feb 2020 08:37:52 -0500

Hi Ludovic,

Ludovic Courtès <[email-masked]> writes:

> Hi Maxim,
>
> Maxim Cournoyer <[email-masked]> skribis:
>
>> Ludovic Courtès <[email-masked]> writes:
>>
>>> Hi Maxim!
>>>
>>> Great to see Btrfs support improving; many people will love that!
>>>
>>> Maxim Cournoyer <[email-masked]> skribis:
>>>
>>>> From 3640bea548826e1c1ec9b766da1fdfe4791d7452 Mon Sep 17 00:00:00 2001
>>>> From: Maxim Cournoyer <[email-masked]>
>>>> Date: Sun, 17 Nov 2019 06:01:00 +0900
>>>> Subject: [PATCH 1/9] gnu: tests: Reduce the time required to run the system
>>>>  tests.
>>>>
>>>> When setting the GUIX_DEV_HACKS environment variable, the Guix package used
>>>> inside the instrumented VMs recycles the binaries already found in the Guix
>>>> checkout of the developer instead of rebuilding Guix from scratch.  This
>>>> brings the time required for this component from 20+ minutes down to 2-3
>>>> minutes on an X200 machine.
>>>>
>>>> * gnu/packages/package-management.scm (current-guix/pre-built): New procedure.
>>>> * build-aux/run-system-tests.scm (tests-for-channel-instance): Use it, when
>>>> GUIX_DEV_HACKS is defined.
>>>
>>> I understand the need, but I’d really like to avoid that; it’s too
>>> fragile IMO.
>>>
>>> But I have good news!  First, commit
>>> 887fd835a7c90f720d36a211478012547feaead0 really improved things by
>>> avoiding the full ‘guix’ package rebuild (and we’re only talking about
>>> the installation tests; other tests are just fine.)  Second, there are
>>> improvements to Guile that will appear in 3.0.1/2.2.7 that make
>>> compilation of big files roughly twice as fast.
>>>
>>> There’s still room for improvement, but I’d rather work in those
>>> directions.  WDYT?
>>
>> With a little bit more love (inheriting from the Guix package from the
>> inferior captured at build time), I don't see the hack being any less
>> fragile than the Guix checkout compiled and ran with ./pre-inst-env.
>
> It’s grabbing files from the working tree, with heuristics to minimize
> the changes in incorporating files that shouldn’t be there; I think it’s
> fragile.  :-)

Fragile or not, it's helped me getting this change tested much faster
than I could have had otherwise, which is the point of that hack :-).
Benchmarks below.

> It also breaks that idea that things compiled by Guix are well under
> control.
>
>> There's no arguing that it *is* a hack, but:
>>
>> 1) Being labeled as such (GUIX_DEV_HACKS)
>> 2) Being undocumented
>> 3) Only being enabled explicitly (through that GUIX_DEV_HACKS
>> environment variable)
>> 4) Can be reverted easily in the future when the default, clean implementation is
>> fast enough to obsolete it.
>>
>> To me means its targeted to developers who understand the nature of the
>> hack and is provided without any warranty.
>>
>> And while it's exciting that Guile's compilation time is going to be
>> improved, no compiler's going to be as efficient as "no compilation"
>> ;-).
>
> True!  But still, we’d have to maintain that in the meantime and deal
> with any “surprising” effects it has for those using it.

Yeah.

> FWIW, when testing (gnu installer tests), I only have to rebuild
> “guix-system-tests.drv”, which is fast.  And in fact, I can also not
> rebuild anything by doing:
>
>   (define operating-system-with-current-guix identity)
>
> because in this particular case, I know it’s not necessary to have the
> current ‘guix’ package.
>
> I suppose this would also be an option in your case, when testing the
> Btrfs changes, no?

I think it is important that the 'installer' image corresponds to the
'current-guix' in my case, because it has to generate the correct GRUB
configuration file at 'guix system init' time.

Below are some analysis of the derivations triggered in different scenarios.

Without the hack:

--8<---------------cut here---------------start------------->8---
./pre-inst-env make check-system TESTS=btrfs-root-on-subvolume-os
Compiling Scheme modules...
random seed for tests: 1581852580
Computing Guix derivation for 'x86_64-linux'... \
Running 1 system tests...
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
The following derivations will be built:
   /gnu/store/3g9bawa6c876lml0318g2knqdcv2ahv9-btrfs-root-on-subvolume-os.drv
   /gnu/store/vswbrzp8ab5wz0fyzrj9j72mqcbd6c4a-installation.drv
   /gnu/store/nf1wd5bgminylzvwq4mjs5293hpr1mmi-disk-image.drv
   /gnu/store/45334hsl3hs5yx13x7qz1b1sc83vkbzj-module-import-compiled.drv
   /gnu/store/dmi03i3jv9wwkw10fm57g7fq97kwlscf-module-import.drv
   /gnu/store/4cp5pqyn554rdmv9l4vfhnw7lgasv18q-raw-initrd.drv
   /gnu/store/vx147spsmrxkiy0qcmvxn341fpz4fmrv-init.drv
   /gnu/store/d6ri0lh953vaksiz5h8jx681h3i35vvm-module-import-compiled.drv
   /gnu/store/b0gv94llsbvrlzkxs3naz7crcv1glxy1-grub.cfg.drv
   /gnu/store/gcslrfymsqsp6kqckla41zkyaa7fy9in-raw-initrd.drv
   /gnu/store/m8bbfcdn1irn7a41syy9arl1yz34hbln-init.drv
   /gnu/store/hbfgqnralir92slqr9hhfw8cxqrlgv06-system.drv
   /gnu/store/0v4aq6yprk8az183rpdjx90jnxw3w838-parameters.drv
   /gnu/store/8daaamb92bbkpdwz96a19r81f7vnk40k-gc-roots.drv
   /gnu/store/f48dwgib52ciaq1nh06nhks6g7gvy7bx-system.drv
   /gnu/store/4ll7vvq5wxq8c2xl8qw5dbim7nrz0yda-raw-initrd.drv
   /gnu/store/mxdfkkfyy3ld6656a01z0lw7gxgjns25-init.drv
   /gnu/store/72fjlv3kp75629as4bc49yp9hgf80pv7-boot.drv
   /gnu/store/xra5iv1ayyiml1kvpcjg5rkrgjbzy6lb-activate.scm.drv
   /gnu/store/xww4xc7rpc1bw1xk9sn6vy3hazjk1gcq-module-import-compiled.drv
   /gnu/store/y8hd9wzr9ypn2pfcl5al0dckijzw36x6-shepherd.conf.drv
   /gnu/store/14mdcbdyqrihnl7x8lqygncxdbsvmhv0-shepherd-file-system--home.go.drv
   /gnu/store/clv6h5sxwgchw1kkf9cnafgvd5ms4p4r-shepherd-file-system--home.scm.drv
   /gnu/store/zc84ngrjdvbc4kibdvzipf9sxjj50rgz-module-import-compiled.drv
   /gnu/store/6cca3yng6k4zl812ysdgmj5lyw8lmwln-shepherd-file-system--gnu-store.go.drv
   /gnu/store/rplp3l38j9jm0fism0ka1iqbfhx7h3ir-shepherd-file-system--gnu-store.scm.drv
   /gnu/store/729f2ranwr6klr90rvrx5pfka30iwazr-shepherd-user-homes.go.drv
   /gnu/store/2cadf4viazfvzlazj996vmbpq3cw1hbr-shepherd-user-homes.scm.drv
   /gnu/store/7j784x4jpxqlcisikn8cin4s0n1vv7z7-shepherd-term-auto.go.drv
   /gnu/store/zgz6p1mss3jwra7d4vzh1dxy9b4llnlg-shepherd-term-auto.scm.drv
   /gnu/store/7n6y2ljl0gp4s568wqbj5iwdkw5hrhk6-shepherd-file-system--dev-shm.go.drv
   /gnu/store/apsplfgbzzq38b5q7p06jxjn37kx74b2-shepherd-file-system--dev-shm.scm.drv
   /gnu/store/qj459c7mlrls9imm1nw98lw9fgqh4yyy-shepherd-udev.go.drv
   /gnu/store/78klph6xipr232a938qjhm8v4qviacvd-shepherd-udev.scm.drv
   /gnu/store/z103dcbbvz3inx6ax7s966zxmy1s38hn-shepherd-file-system--dev-pts.go.drv
   /gnu/store/5ss1d8nwn4dv9vb69h1iyw884b61y487-shepherd-file-system--dev-pts.scm.drv
   /gnu/store/z1f6a7gfxxszaa0lm68xfl9hbglz48cw-parameters.drv
   /gnu/store/vvg05l3pgkyz1rky6f2cn0d1r2i1b6yr-system.drv
   /gnu/store/1k5k3kd11l3wabcc8sci8m04nvc6wllw-raw-initrd.drv
   /gnu/store/51ay1gi0ajsbrgm7wy6j1njyy6pcjlzb-init.drv
   /gnu/store/jjhnm39rqckl6r0jf7l43000nlydb2vj-parameters.drv
   /gnu/store/wdm0acks0pzl3hiam7knffl7n6xmyvrm-boot.drv
   /gnu/store/59mhndnjhsq6yspag4miv4b71rb8v683-activate.scm.drv
   /gnu/store/z0ik75q9nshaik97jsigd69vriyjijgp-shepherd.conf.drv
   /gnu/store/6pxsd37k5nl5viqadd57n0hah53nzcp7-shepherd-user-homes.go.drv
   /gnu/store/y9rj23r1xmyb5b4fwrh75pb5yr61clvp-shepherd-user-homes.scm.drv
   /gnu/store/h0xbdk4hw1i4byy8xnrnaqmlwnfgrswz-profile.drv
   /gnu/store/sxdgmvfjakapmbyqmxjgvarsaaxc2mw7-profile.drv
   /gnu/store/hxcadzr771dzl99kylz64d9qz2qai8wd-guix-000000000.drv
   /gnu/store/95lcx1xx41p4vcwqlwli7phny6hpp8b0-guix-manual.drv
   /gnu/store/9yz0spp1h158zdh8wmg2r7sspnkm0qfc-guix-translated-texinfo.drv
   /gnu/store/g6ggidnpaahws37qgx15mvkhfll0ns06-guix-daemon.drv
   /gnu/store/jpb2jfk00q5nh5fg3k3cf6hcyw49zz84-guix-command.drv
   /gnu/store/14zcma6hkqszaab37hda736i24r41rv4-guix-module-union.drv
   /gnu/store/sfzd86425cl744lr58yh877i7z5qbd68-guix-000000000-modules.drv
   /gnu/store/71a40hzi2d2wdn1vjl5amfq00caqlh3m-guix-system-tests-modules.drv
   /gnu/store/kc3zg69yabaglvllj4l7hzgs72v9mk26-guix-system-tests.drv
   /gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv
   /gnu/store/d7df7qw5allqcm2qn75dn60wz1dg50cq-guix-system.drv
   /gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv
   /gnu/store/xgpy1v810xi76w8ivpfi7gg5h7vg0ska-guix-cli.drv
   /gnu/store/7ih7cmbhz1p7a4m7yrgy0s2jawqc666n-guix-packages-base-modules.drv
   /gnu/store/j15kzs5m07pq3nmgqr5rr47cryq8arfs-guix-system-modules.drv
   /gnu/store/rhk9cknm5wbk30slzzrr52app8mfn4a2-guix-packages-modules.drv
   /gnu/store/x05mz632h3ph0k9n3s5y14m51qy3k929-guix-cli-modules.drv
   /gnu/store/fs2g9iin23iq4505jsxjnrjaxnxp1wzl-inferior-script.scm.drv
   /gnu/store/y4hv2s267zjz2gzja3cj428a7z1dln98-profile.drv
   /gnu/store/kx5h4kxkz28gahlgkxni02i0rf8558vd-boot.drv
   /gnu/store/nhi2s5zcyd5frjqag4jnp7fvhzbx6kd6-activate.scm.drv
   /gnu/store/qnchikcfqx8hn0a7cn45f0pnf664s0jk-shepherd.conf.drv
   /gnu/store/7n4cqlsbn7hywlwssxvax6j6b57gm1q4-shepherd-user-homes.go.drv
   /gnu/store/dl333r3dshzi5nb4qqrvcsp2hmk3hd9p-shepherd-user-homes.scm.drv
   /gnu/store/i96lsb7shixcczc62bfadbg1g73qp38l-shepherd-udev.go.drv
   /gnu/store/yv3maqmnqqpiqj2jk5ss574pzvgh9jin-shepherd-udev.scm.drv
   /gnu/store/s5w901l6zl0ql800bc9cndnskqdhnsxm-shepherd-file-system--tmp.go.drv
   /gnu/store/a5nb6vhs86g76ww5bmpphi398pggnga7-shepherd-file-system--tmp.scm.drv
   /gnu/store/sjn7zb56x72lh6i7arkh6gpd639g7d17-shepherd-guix-daemon.go.drv
   /gnu/store/rww6z6m3nz6s7h54xklwj3plylg1f0yc-shepherd-guix-daemon.scm.drv
   /gnu/store/lmbja82mymwsn3kmxwfy8g7s46xac443-linux-vm-loader.drv
   /gnu/store/z8y0v374himjlig4qwjisv1xa7rk7r0l-builder-in-linux-vm.drv
   /gnu/store/14bw0x4dq0g262vk4pjh3dlha6x3gz0s-module-import-compiled.drv
   /gnu/store/nbkfy5wjpia5y7hj1p9j5hmbv42j4zp5-module-import.drv
The following grafts will be made:
   /gnu/store/qn8j1cqp2lfvghiv4sy5rps4kv2hz02y-guile3.0-git-0.3.0.drv
   /gnu/store/dnl877iincgcw7lw493h5nd4llxqjw7a-libgit2-0.28.4.drv
The following profile hooks will be built:
   /gnu/store/96274clz8449s7s18a91sa31d1ilmi0p-fonts-dir.drv
   /gnu/store/30lvdbci7v9zqgn3nqjy1vgbpv5k4b98-ca-certificate-bundle.drv
   /gnu/store/b5dspr8576n0j3vl2cjsr7zrfdp380cw-guix-package-cache.drv
   /gnu/store/chjdvqjbrnb7cqla43n5rvqia5d4f4mg-fonts-dir.drv
   /gnu/store/kh7wixk3i5db2ym48ddyrdbggw8ccxp8-info-dir.drv
   /gnu/store/x3bp2acfy04w9r9l11w30l9z0hpsii5a-manual-database.drv
   /gnu/store/bhla9fihy35pgc3bwszfxvsfjir71v88-glib-schemas.drv
   /gnu/store/isb4444058amfr4sipqmffcrgisx75gs-ca-certificate-bundle.drv
   /gnu/store/l8qgqaxq1xcb8jk3lqmzzrfiv8hzpna1-xdg-desktop-database.drv
   /gnu/store/x0vhd98kg66pzfwffbi45f76126by816-xdg-mime-database.drv
   /gnu/store/xs4k7nmrpbjsy0a5k6lsbdxc2n4i23g4-info-dir.drv
   /gnu/store/zffqfc9w73sy815av7hwincbqpl7hbkr-manual-database.drv
building /gnu/store/dmi03i3jv9wwkw10fm57g7fq97kwlscf-module-import.drv...
successfully built /gnu/store/dmi03i3jv9wwkw10fm57g7fq97kwlscf-module-import.drv
building /gnu/store/9yz0spp1h158zdh8wmg2r7sspnkm0qfc-guix-translated-texinfo.drv...
^Cmake: *** [Makefile:5711: check-system] Interrupt
--8<---------------cut here---------------end--------------->8---

With the hack:

--8<---------------cut here---------------start------------->8---
./pre-inst-env make check-system TESTS=btrfs-root-on-subvolume-os GUIX_DEV_HACKS=1
Compiling Scheme modules...
random seed for tests: 1581851372
Running 1 system tests...
The following derivations will be built:
   /gnu/store/l4z1363klr8a58qmm3pjzy2y5bxsr6bd-btrfs-root-on-subvolume-os.drv
   /gnu/store/zlg6gxml4awbkbs2s6n1b0z3ysrqvy0h-installation.drv
   /gnu/store/89vdpn33f47y0510im604snwfmbpswmm-disk-image.drv
   /gnu/store/45334hsl3hs5yx13x7qz1b1sc83vkbzj-module-import-compiled.drv
   /gnu/store/4cp5pqyn554rdmv9l4vfhnw7lgasv18q-raw-initrd.drv
   /gnu/store/vx147spsmrxkiy0qcmvxn341fpz4fmrv-init.drv
   /gnu/store/d6ri0lh953vaksiz5h8jx681h3i35vvm-module-import-compiled.drv
   /gnu/store/58912rdjjk4jdv767svb2axp0llmn8ch-linux-vm-loader.drv
   /gnu/store/hvcm9abi0br38plwpngqlvw1l0060fni-builder-in-linux-vm.drv
   /gnu/store/14bw0x4dq0g262vk4pjh3dlha6x3gz0s-module-import-compiled.drv
   /gnu/store/nbkfy5wjpia5y7hj1p9j5hmbv42j4zp5-module-import.drv
   /gnu/store/shc8hzzqi40pdpip0773i2g9x2apnn0h-grub.cfg.drv
   /gnu/store/gcslrfymsqsp6kqckla41zkyaa7fy9in-raw-initrd.drv
   /gnu/store/m8bbfcdn1irn7a41syy9arl1yz34hbln-init.drv
   /gnu/store/zifmvsbiw6x4gs15k29l1nvyzxkszafw-system.drv
   /gnu/store/0v4aq6yprk8az183rpdjx90jnxw3w838-parameters.drv
   /gnu/store/8daaamb92bbkpdwz96a19r81f7vnk40k-gc-roots.drv
   /gnu/store/f48dwgib52ciaq1nh06nhks6g7gvy7bx-system.drv
   /gnu/store/4ll7vvq5wxq8c2xl8qw5dbim7nrz0yda-raw-initrd.drv
   /gnu/store/mxdfkkfyy3ld6656a01z0lw7gxgjns25-init.drv
   /gnu/store/72fjlv3kp75629as4bc49yp9hgf80pv7-boot.drv
   /gnu/store/xra5iv1ayyiml1kvpcjg5rkrgjbzy6lb-activate.scm.drv
   /gnu/store/xww4xc7rpc1bw1xk9sn6vy3hazjk1gcq-module-import-compiled.drv
   /gnu/store/y8hd9wzr9ypn2pfcl5al0dckijzw36x6-shepherd.conf.drv
   /gnu/store/14mdcbdyqrihnl7x8lqygncxdbsvmhv0-shepherd-file-system--home.go.drv
   /gnu/store/clv6h5sxwgchw1kkf9cnafgvd5ms4p4r-shepherd-file-system--home.scm.drv
   /gnu/store/zc84ngrjdvbc4kibdvzipf9sxjj50rgz-module-import-compiled.drv
   /gnu/store/6cca3yng6k4zl812ysdgmj5lyw8lmwln-shepherd-file-system--gnu-store.go.drv
   /gnu/store/rplp3l38j9jm0fism0ka1iqbfhx7h3ir-shepherd-file-system--gnu-store.scm.drv
   /gnu/store/729f2ranwr6klr90rvrx5pfka30iwazr-shepherd-user-homes.go.drv
   /gnu/store/2cadf4viazfvzlazj996vmbpq3cw1hbr-shepherd-user-homes.scm.drv
   /gnu/store/7j784x4jpxqlcisikn8cin4s0n1vv7z7-shepherd-term-auto.go.drv
   /gnu/store/zgz6p1mss3jwra7d4vzh1dxy9b4llnlg-shepherd-term-auto.scm.drv
   /gnu/store/7n6y2ljl0gp4s568wqbj5iwdkw5hrhk6-shepherd-file-system--dev-shm.go.drv
   /gnu/store/apsplfgbzzq38b5q7p06jxjn37kx74b2-shepherd-file-system--dev-shm.scm.drv
   /gnu/store/qj459c7mlrls9imm1nw98lw9fgqh4yyy-shepherd-udev.go.drv
   /gnu/store/78klph6xipr232a938qjhm8v4qviacvd-shepherd-udev.scm.drv
   /gnu/store/z103dcbbvz3inx6ax7s966zxmy1s38hn-shepherd-file-system--dev-pts.go.drv
   /gnu/store/5ss1d8nwn4dv9vb69h1iyw884b61y487-shepherd-file-system--dev-pts.scm.drv
   /gnu/store/z1f6a7gfxxszaa0lm68xfl9hbglz48cw-parameters.drv
   /gnu/store/vvg05l3pgkyz1rky6f2cn0d1r2i1b6yr-system.drv
   /gnu/store/1k5k3kd11l3wabcc8sci8m04nvc6wllw-raw-initrd.drv
   /gnu/store/51ay1gi0ajsbrgm7wy6j1njyy6pcjlzb-init.drv
   /gnu/store/jjhnm39rqckl6r0jf7l43000nlydb2vj-parameters.drv
   /gnu/store/wdm0acks0pzl3hiam7knffl7n6xmyvrm-boot.drv
   /gnu/store/59mhndnjhsq6yspag4miv4b71rb8v683-activate.scm.drv
   /gnu/store/z0ik75q9nshaik97jsigd69vriyjijgp-shepherd.conf.drv
   /gnu/store/6pxsd37k5nl5viqadd57n0hah53nzcp7-shepherd-user-homes.go.drv
   /gnu/store/y9rj23r1xmyb5b4fwrh75pb5yr61clvp-shepherd-user-homes.scm.drv
   /gnu/store/kammkm5z0ihjqalg0ijn69ffhdyzki47-profile.drv
   /gnu/store/07kxlp8a99mvx2zidnlz6rm4ak2az8d0-guix-1.0.1-13.50299ad+.drv
   /gnu/store/m9783fc7m360dk582b3mv2wgrsdz6amk-boot.drv
   /gnu/store/3v1whxi5qkp9cyfc3vjpvziwc9ms7y7k-shepherd.conf.drv
   /gnu/store/50halfax0zbiwpy47z6374ybh1mq1d5r-shepherd-guix-daemon.go.drv
   /gnu/store/g4m4mqiz9z4yd2iwzmb6f81vidw0k4bg-shepherd-guix-daemon.scm.drv
   /gnu/store/7n4cqlsbn7hywlwssxvax6j6b57gm1q4-shepherd-user-homes.go.drv
   /gnu/store/dl333r3dshzi5nb4qqrvcsp2hmk3hd9p-shepherd-user-homes.scm.drv
   /gnu/store/i96lsb7shixcczc62bfadbg1g73qp38l-shepherd-udev.go.drv
   /gnu/store/yv3maqmnqqpiqj2jk5ss574pzvgh9jin-shepherd-udev.scm.drv
   /gnu/store/s5w901l6zl0ql800bc9cndnskqdhnsxm-shepherd-file-system--tmp.go.drv
   /gnu/store/a5nb6vhs86g76ww5bmpphi398pggnga7-shepherd-file-system--tmp.scm.drv
   /gnu/store/nhi2s5zcyd5frjqag4jnp7fvhzbx6kd6-activate.scm.drv
The following profile hooks will be built:
   /gnu/store/4j2hrilvx5rfycqs1sccd39jy5yjhxy0-xdg-mime-database.drv
   /gnu/store/4rdg1bi6xxn85zq5cjqc3bdfksx14913-info-dir.drv
   /gnu/store/c59p1krnc51qlbr5vnxjx6bg3rrixca4-glib-schemas.drv
   /gnu/store/drf1pi6m91b6qra3p6hrknfzh7gcd51z-fonts-dir.drv
   /gnu/store/fwal8vsrjzpbwljnihvv66k9ikkfx2ma-xdg-desktop-database.drv
   /gnu/store/jzp4ps09ipy0kcc6ybx5967vi3xlq7aa-manual-database.drv
   /gnu/store/m7yl2xvk07l37l19wp2hfbvhzl3583ji-ca-certificate-bundle.drv
building /gnu/store/45334hsl3hs5yx13x7qz1b1sc83vkbzj-module-import-compiled.drv...
process 21756 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 0.0 (normalized: 0.0)
building /gnu/store/07kxlp8a99mvx2zidnlz6rm4ak2az8d0-guix-1.0.1-13.50299ad+.drv...
^Cmake: *** [Makefile:5711: check-system] Interrupt
--8<---------------cut here---------------end--------------->8---

The diff between those two looks like:
--8<---------------cut here---------------start------------->8---
--- /tmp/ediffD0RQCf	2020-02-16 12:10:53.643411325 -0500
+++ /tmp/ediffKmWrdZ	2020-02-16 12:10:53.647411377 -0500
@@ -1,15 +1,18 @@
-   /gnu/store/3g9bawa6c876lml0318g2knqdcv2ahv9-btrfs-root-on-subvolume-os.drv
-   /gnu/store/vswbrzp8ab5wz0fyzrj9j72mqcbd6c4a-installation.drv
-   /gnu/store/nf1wd5bgminylzvwq4mjs5293hpr1mmi-disk-image.drv
+   /gnu/store/l4z1363klr8a58qmm3pjzy2y5bxsr6bd-btrfs-root-on-subvolume-os.drv
+   /gnu/store/zlg6gxml4awbkbs2s6n1b0z3ysrqvy0h-installation.drv
+   /gnu/store/89vdpn33f47y0510im604snwfmbpswmm-disk-image.drv
    /gnu/store/45334hsl3hs5yx13x7qz1b1sc83vkbzj-module-import-compiled.drv
-   /gnu/store/dmi03i3jv9wwkw10fm57g7fq97kwlscf-module-import.drv
    /gnu/store/4cp5pqyn554rdmv9l4vfhnw7lgasv18q-raw-initrd.drv
    /gnu/store/vx147spsmrxkiy0qcmvxn341fpz4fmrv-init.drv
    /gnu/store/d6ri0lh953vaksiz5h8jx681h3i35vvm-module-import-compiled.drv
-   /gnu/store/b0gv94llsbvrlzkxs3naz7crcv1glxy1-grub.cfg.drv
+   /gnu/store/58912rdjjk4jdv767svb2axp0llmn8ch-linux-vm-loader.drv
+   /gnu/store/hvcm9abi0br38plwpngqlvw1l0060fni-builder-in-linux-vm.drv
+   /gnu/store/14bw0x4dq0g262vk4pjh3dlha6x3gz0s-module-import-compiled.drv
+   /gnu/store/nbkfy5wjpia5y7hj1p9j5hmbv42j4zp5-module-import.drv
+   /gnu/store/shc8hzzqi40pdpip0773i2g9x2apnn0h-grub.cfg.drv
    /gnu/store/gcslrfymsqsp6kqckla41zkyaa7fy9in-raw-initrd.drv
    /gnu/store/m8bbfcdn1irn7a41syy9arl1yz34hbln-init.drv
-   /gnu/store/hbfgqnralir92slqr9hhfw8cxqrlgv06-system.drv
+   /gnu/store/zifmvsbiw6x4gs15k29l1nvyzxkszafw-system.drv
    /gnu/store/0v4aq6yprk8az183rpdjx90jnxw3w838-parameters.drv
    /gnu/store/8daaamb92bbkpdwz96a19r81f7vnk40k-gc-roots.drv
    /gnu/store/f48dwgib52ciaq1nh06nhks6g7gvy7bx-system.drv
@@ -44,56 +47,24 @@
    /gnu/store/z0ik75q9nshaik97jsigd69vriyjijgp-shepherd.conf.drv
    /gnu/store/6pxsd37k5nl5viqadd57n0hah53nzcp7-shepherd-user-homes.go.drv
    /gnu/store/y9rj23r1xmyb5b4fwrh75pb5yr61clvp-shepherd-user-homes.scm.drv
-   /gnu/store/h0xbdk4hw1i4byy8xnrnaqmlwnfgrswz-profile.drv
-   /gnu/store/sxdgmvfjakapmbyqmxjgvarsaaxc2mw7-profile.drv
-   /gnu/store/hxcadzr771dzl99kylz64d9qz2qai8wd-guix-000000000.drv
-   /gnu/store/95lcx1xx41p4vcwqlwli7phny6hpp8b0-guix-manual.drv
-   /gnu/store/9yz0spp1h158zdh8wmg2r7sspnkm0qfc-guix-translated-texinfo.drv
-   /gnu/store/g6ggidnpaahws37qgx15mvkhfll0ns06-guix-daemon.drv
-   /gnu/store/jpb2jfk00q5nh5fg3k3cf6hcyw49zz84-guix-command.drv
-   /gnu/store/14zcma6hkqszaab37hda736i24r41rv4-guix-module-union.drv
-   /gnu/store/sfzd86425cl744lr58yh877i7z5qbd68-guix-000000000-modules.drv
-   /gnu/store/71a40hzi2d2wdn1vjl5amfq00caqlh3m-guix-system-tests-modules.drv
-   /gnu/store/kc3zg69yabaglvllj4l7hzgs72v9mk26-guix-system-tests.drv
-   /gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv
-   /gnu/store/d7df7qw5allqcm2qn75dn60wz1dg50cq-guix-system.drv
-   /gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv
-   /gnu/store/xgpy1v810xi76w8ivpfi7gg5h7vg0ska-guix-cli.drv
-   /gnu/store/7ih7cmbhz1p7a4m7yrgy0s2jawqc666n-guix-packages-base-modules.drv
-   /gnu/store/j15kzs5m07pq3nmgqr5rr47cryq8arfs-guix-system-modules.drv
-   /gnu/store/rhk9cknm5wbk30slzzrr52app8mfn4a2-guix-packages-modules.drv
-   /gnu/store/x05mz632h3ph0k9n3s5y14m51qy3k929-guix-cli-modules.drv
-   /gnu/store/fs2g9iin23iq4505jsxjnrjaxnxp1wzl-inferior-script.scm.drv
-   /gnu/store/y4hv2s267zjz2gzja3cj428a7z1dln98-profile.drv
-   /gnu/store/kx5h4kxkz28gahlgkxni02i0rf8558vd-boot.drv
-   /gnu/store/nhi2s5zcyd5frjqag4jnp7fvhzbx6kd6-activate.scm.drv
-   /gnu/store/qnchikcfqx8hn0a7cn45f0pnf664s0jk-shepherd.conf.drv
+   /gnu/store/kammkm5z0ihjqalg0ijn69ffhdyzki47-profile.drv
+   /gnu/store/07kxlp8a99mvx2zidnlz6rm4ak2az8d0-guix-1.0.1-13.50299ad+.drv
+   /gnu/store/m9783fc7m360dk582b3mv2wgrsdz6amk-boot.drv
+   /gnu/store/3v1whxi5qkp9cyfc3vjpvziwc9ms7y7k-shepherd.conf.drv
+   /gnu/store/50halfax0zbiwpy47z6374ybh1mq1d5r-shepherd-guix-daemon.go.drv
+   /gnu/store/g4m4mqiz9z4yd2iwzmb6f81vidw0k4bg-shepherd-guix-daemon.scm.drv
    /gnu/store/7n4cqlsbn7hywlwssxvax6j6b57gm1q4-shepherd-user-homes.go.drv
    /gnu/store/dl333r3dshzi5nb4qqrvcsp2hmk3hd9p-shepherd-user-homes.scm.drv
    /gnu/store/i96lsb7shixcczc62bfadbg1g73qp38l-shepherd-udev.go.drv
    /gnu/store/yv3maqmnqqpiqj2jk5ss574pzvgh9jin-shepherd-udev.scm.drv
    /gnu/store/s5w901l6zl0ql800bc9cndnskqdhnsxm-shepherd-file-system--tmp.go.drv
    /gnu/store/a5nb6vhs86g76ww5bmpphi398pggnga7-shepherd-file-system--tmp.scm.drv
-   /gnu/store/sjn7zb56x72lh6i7arkh6gpd639g7d17-shepherd-guix-daemon.go.drv
-   /gnu/store/rww6z6m3nz6s7h54xklwj3plylg1f0yc-shepherd-guix-daemon.scm.drv
-   /gnu/store/lmbja82mymwsn3kmxwfy8g7s46xac443-linux-vm-loader.drv
-   /gnu/store/z8y0v374himjlig4qwjisv1xa7rk7r0l-builder-in-linux-vm.drv
-   /gnu/store/14bw0x4dq0g262vk4pjh3dlha6x3gz0s-module-import-compiled.drv
-   /gnu/store/nbkfy5wjpia5y7hj1p9j5hmbv42j4zp5-module-import.drv
-The following grafts will be made:
-   /gnu/store/qn8j1cqp2lfvghiv4sy5rps4kv2hz02y-guile3.0-git-0.3.0.drv
-   /gnu/store/dnl877iincgcw7lw493h5nd4llxqjw7a-libgit2-0.28.4.drv
+   /gnu/store/nhi2s5zcyd5frjqag4jnp7fvhzbx6kd6-activate.scm.drv
 The following profile hooks will be built:
-   /gnu/store/96274clz8449s7s18a91sa31d1ilmi0p-fonts-dir.drv
-   /gnu/store/30lvdbci7v9zqgn3nqjy1vgbpv5k4b98-ca-certificate-bundle.drv
-   /gnu/store/b5dspr8576n0j3vl2cjsr7zrfdp380cw-guix-package-cache.drv
-   /gnu/store/chjdvqjbrnb7cqla43n5rvqia5d4f4mg-fonts-dir.drv
-   /gnu/store/kh7wixk3i5db2ym48ddyrdbggw8ccxp8-info-dir.drv
-   /gnu/store/x3bp2acfy04w9r9l11w30l9z0hpsii5a-manual-database.drv
-   /gnu/store/bhla9fihy35pgc3bwszfxvsfjir71v88-glib-schemas.drv
-   /gnu/store/isb4444058amfr4sipqmffcrgisx75gs-ca-certificate-bundle.drv
-   /gnu/store/l8qgqaxq1xcb8jk3lqmzzrfiv8hzpna1-xdg-desktop-database.drv
-   /gnu/store/x0vhd98kg66pzfwffbi45f76126by816-xdg-mime-database.drv
-   /gnu/store/xs4k7nmrpbjsy0a5k6lsbdxc2n4i23g4-info-dir.drv
-   /gnu/store/zffqfc9w73sy815av7hwincbqpl7hbkr-manual-database.drv
-building /gnu/store/dmi03i3jv9wwkw10fm57g7fq97kwlscf-module-import.drv...
+   /gnu/store/4j2hrilvx5rfycqs1sccd39jy5yjhxy0-xdg-mime-database.drv
+   /gnu/store/4rdg1bi6xxn85zq5cjqc3bdfksx14913-info-dir.drv
+   /gnu/store/c59p1krnc51qlbr5vnxjx6bg3rrixca4-glib-schemas.drv
+   /gnu/store/drf1pi6m91b6qra3p6hrknfzh7gcd51z-fonts-dir.drv
+   /gnu/store/fwal8vsrjzpbwljnihvv66k9ikkfx2ma-xdg-desktop-database.drv
+   /gnu/store/jzp4ps09ipy0kcc6ybx5967vi3xlq7aa-manual-database.drv
+   /gnu/store/m7yl2xvk07l37l19wp2hfbvhzl3583ji-ca-certificate-bundle.drv
--8<---------------cut here---------------end--------------->8---

So, we can see there would me many guix-* things to build without the
hack.

Just building the OS using guix-current/pre-built, vs old
guix-current', vs the modern guix-current used for system tests:

guix-current/pre-built:
--8<---------------cut here---------------start------------->8---
time ./pre-inst-env guix system build -e '(begin (use-modules (gnu packages package-management)) (parameterize ((current-guix-package (current-guix/pre-built))) ((@@ (gnu tests install) operating-system-with-current-guix) (@@ (gnu tests install) %btrfs-root-on-subvolume-os))))'
[...]
real    12m23.259s
user    0m9.124s
sys     0m0.986s
--8<---------------cut here---------------end--------------->8---

old guix-current:
--8<---------------cut here---------------start------------->8---
time ./pre-inst-env guix system build -e '(begin (use-modules (gnu packages package-management)) (parameterize ((current-guix-package (current-guix))) ((@@ (gnu tests install) operating-system-with-current-guix) (@@ (gnu tests install) %btrfs-root-on-subvolume-os))))'
[...]
real    45m45.572s
user    0m10.428s
sys     0m1.279s
--8<---------------cut here---------------end--------------->8---

And with the new "guix-current", computed with (guix self):
--8<---------------cut here---------------start------------->8---
time ./pre-inst-env guix system build -e '(begin
>          (use-modules ((gnu ci) #:select (channel-instance->package))
>         (guix monads)
>         (guix channels)
>         (guix store)
>         ((guix status) #:select (with-status-verbosity))
>         ((guix git-download) #:select (git-predicate))
>         (guix utils)
>         (gnu packages package-management))
>          (with-store store
>     (with-status-verbosity 2
>       (run-with-store store
>         (mlet* %store-monad
>      ((source-dir -> "/home/maxim/src/guix")
>       (source (interned-file source-dir
>         "guix-source"
>         #:recursive? #t
>         #:select? (or (git-predicate
>          source-dir)
>                (const #t))))
>       (instance -> (checkout->channel-instance source))
>       (new-guix-current -> (channel-instance->package instance)))
>           (return  (parameterize ((current-guix-package new-guix-current))
>        ((@@ (gnu tests install) operating-system-with-current-guix)
>         (@@ (gnu tests install) %btrfs-root-on-subvolume-os)))))))))'

substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
The following file will be downloaded:
   /gnu/store/7r7lbghps6qcl10qb6m321a3bgpr72fi-compute-guix-derivation
substituting /gnu/store/7r7lbghps6qcl10qb6m321a3bgpr72fi-compute-guix-derivation...
downloading from http://10.42.0.199/nar/gzip/7r7lbghps6qcl10qb6m321a3bgpr72fi-compute-guix-derivation...
 compute-guix-derivation                                                                                                                                                           124KiB/s 00:00 | 881B transferred

substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
\
substitute: updating substitutes from 'http://10.42.0.199:80'... 100.0%
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
The following derivations will be built:
   /gnu/store/1kmbdnkdip0xbdi4h09jj44nccmpmxh6-system.drv
   /gnu/store/a2dl48yn635qqbga72gwkqnypd45lxaf-profile.drv
   /gnu/store/3rqfd301xgwlaacwppswdxshlc13ky7p-profile.drv
   /gnu/store/2hd5a6klgq8zz22rsm3jd4wqw6cbcmbq-profile.drv
   /gnu/store/hb87zw934jkgxwkgbbfykwaq55p6pzlq-guix-000000000.drv
   /gnu/store/65dva2y1zq173i93z57xzffn34rmfbgw-guix-daemon.drv
   /gnu/store/cjzvm56h61zhwd56g1ksi91spq567b4b-guix-command.drv
   /gnu/store/flii6im368mj1mlwb1xmnvwhibll0acg-guix-module-union.drv
   /gnu/store/mx5kd00k1axs9xrgwn5hibiidbxshy3g-guix-000000000-modules.drv
   /gnu/store/7ih7cmbhz1p7a4m7yrgy0s2jawqc666n-guix-packages-base-modules.drv
   /gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv
   /gnu/store/rhk9cknm5wbk30slzzrr52app8mfn4a2-guix-packages-modules.drv
   /gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv
   /gnu/store/ybxk6d3bccnz52d2s55gcang7795cy3l-guix-cli-modules.drv
   /gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv
   /gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv
   /gnu/store/ysr4d2bqhs4c4viwyk9pvcjcnwv4pnr8-guix-system-tests-modules.drv
   /gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv
   /gnu/store/z3mzdfm2x2jrab7g3yhcg06lrgpq2ijz-guix-system-modules.drv
   /gnu/store/95lcx1xx41p4vcwqlwli7phny6hpp8b0-guix-manual.drv
   /gnu/store/9yz0spp1h158zdh8wmg2r7sspnkm0qfc-guix-translated-texinfo.drv
   /gnu/store/zdqspx48gmwa9xv2ibn993qfswq9zgkf-inferior-script.scm.drv
   /gnu/store/ixk9m5hqwj42kdzh88vwy06alk9bw811-boot.drv
   /gnu/store/jp62bqlvch38sqcqkxk3ddwih84qz8ka-shepherd.conf.drv
   /gnu/store/7wkb1al9lxp5k84k9b1i5v7h69x9p3wr-shepherd-guix-daemon.go.drv
   /gnu/store/5688khnjjabnh8bnn4hc41j05h1larh9-shepherd-guix-daemon.scm.drv
The following grafts will be made:
   /gnu/store/qn8j1cqp2lfvghiv4sy5rps4kv2hz02y-guile3.0-git-0.3.0.drv
   /gnu/store/dnl877iincgcw7lw493h5nd4llxqjw7a-libgit2-0.28.4.drv
The following profile hooks will be built:
   /gnu/store/1li6nkn0p7zikf5y36ljir2n53rf81cg-fonts-dir.drv
   /gnu/store/841rih0j6iskwdxvay7cm94l3vn4idl7-guix-package-cache.drv
   /gnu/store/8k7vn4fbwqvlmhsv604v7zkgils5j0f4-manual-database.drv
   /gnu/store/qc53qlnzwxlhlm01fxp45ppdnrzw0lfz-info-dir.drv
   /gnu/store/qpcnvr43c5rl6bgpsj7l3m38r6xndz7j-ca-certificate-bundle.drv
   /gnu/store/scm0rsny7n5kmryffp081hdh6rh2659l-fonts-dir.drv
   /gnu/store/44wi6c2lq0mpkmx940wsi56fmxr8fjh4-ca-certificate-bundle.drv
   /gnu/store/d80j7mvj59m6h33m3c72mwfckb9xrn7r-info-dir.drv
   /gnu/store/x1cfgs17hpiw33fpq8gj51ldykf8wd25-manual-database.drv
building /gnu/store/9yz0spp1h158zdh8wmg2r7sspnkm0qfc-guix-translated-texinfo.drv...
Your input po file ./guix-manual.de.po seems outdated (The amount of entries differ between files: 7994 is not 8473
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.de.po seems outdated (The amount of entries differ between files: 7994 is not 281
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.es.po seems outdated (The amount of entries differ between files: 7994 is not 8473
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.es.po seems outdated (The amount of entries differ between files: 7994 is not 281
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.fr.po seems outdated (The amount of entries differ between files: 7994 is not 8473
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.fr.po seems outdated (The amount of entries differ between files: 7994 is not 281
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.ru.po seems outdated (The amount of entries differ between files: 7994 is not 8473
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.ru.po seems outdated (The amount of entries differ between files: 7994 is not 281
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.zh_CN.po seems outdated (The amount of entries differ between files: 7994 is not 8473
). Please consider running po4a-updatepo to refresh it.
Your input po file ./guix-manual.zh_CN.po seems outdated (The amount of entries differ between files: 7994 is not 281
). Please consider running po4a-updatepo to refresh it.
successfully built /gnu/store/9yz0spp1h158zdh8wmg2r7sspnkm0qfc-guix-translated-texinfo.drv
applying 2 grafts for /gnu/store/dnl877iincgcw7lw493h5nd4llxqjw7a-libgit2-0.28.4.drv...
grafting '/gnu/store/mqlwm1gfp1wz7i74z2rifv51hscl2201-libgit2-0.28.4' -> '/gnu/store/7ymrcgnz6v4x1krljh60za1fx0wz57ny-libgit2-0.28.4'...
successfully built /gnu/store/dnl877iincgcw7lw493h5nd4llxqjw7a-libgit2-0.28.4.drv
building /gnu/store/95lcx1xx41p4vcwqlwli7phny6hpp8b0-guix-manual.drv...
./guix.de.texi:2286: warning: @node name should not contain `,': Tastaturbelegung, Netzwerkanbindung und Partitionierung
./guix.de.texi:29751: warning: @node name should not contain `,': Vorbereitung, um die Bootstrap-Bin�rdateien zu verwenden
./guix.ru.texi:932: warning: accent command `@,' must not be followed by whitespace
Wide character in warn at /gnu/store/irj21yhgls637jhhkb5yr79s76c96maq-texinfo-6.6/bin/makeinfo line 656.
./guix.ru.texi:3977: warning: `.' or `,' must follow @xref, not д
successfully built /gnu/store/95lcx1xx41p4vcwqlwli7phny6hpp8b0-guix-manual.drv
applying 1 graft for /gnu/store/qn8j1cqp2lfvghiv4sy5rps4kv2hz02y-guile3.0-git-0.3.0.drv...
grafting '/gnu/store/qi80syzn4dhxbwwwlqlww5v042kfkmx3-guile3.0-git-0.3.0' -> '/gnu/store/1hapil0ym1k3cii3j95pmabgnxi7c9m0-guile3.0-git-0.3.0'...
successfully built /gnu/store/qn8j1cqp2lfvghiv4sy5rps4kv2hz02y-guile3.0-git-0.3.0.drv
process 5055 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 0.0 (normalized: 0.0)
building /gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv...
sending 23 store items (54 MiB) to '10.42.0.199'...
exporting path `/gnu/store/c2mxnc0dvi88dq5iacq78xchlcp6f2d2-guix-packages-base-source'
exporting path `/gnu/store/d3s80rm5pyggyqk71mwrsqzqahjc8jqr-guix-packages-base-builder'
exporting path `/gnu/store/4rjdijy36w6zx99bgqlb40nawipcm4w1-libgit2-0.28.4-guile-builder'
exporting path `/gnu/store/w7xwnvv15b6s062jfaqkwnry7padw936-http-parser-2.9.3-checkout.drv'
exporting path `/gnu/store/v6p9i2alpmsldsbjnq2g46rrnn2kwvvg-http-parser-2.9.3.drv'
exporting path `/gnu/store/29l03448v04pniv0rjlmclag9ga66yj6-libgit2-0.28.4.drv'
exporting path `/gnu/store/j823iyw1c851wmmlfbb8vxyy4hcvqcdz-libgit2-0.28.4-guile-builder'
exporting path `/gnu/store/dnl877iincgcw7lw493h5nd4llxqjw7a-libgit2-0.28.4.drv'
exporting path `/gnu/store/i63fzcsg2qrzkj53ri3jglzg1jqxcg6q-guile3.0-git-0.3.0-guile-builder'
exporting path `/gnu/store/ls7zbcnzl4khfqb64nm9nd9yri1x4mwi-guile3.0-git-0.3.0-guile-builder'
exporting path `/gnu/store/rp09b776n1a98fbpy1cbw6v7np66x3b6-guile3.0-git-0.3.0.drv'
exporting path `/gnu/store/qn8j1cqp2lfvghiv4sy5rps4kv2hz02y-guile3.0-git-0.3.0.drv'
exporting path `/gnu/store/rsc33ni89kzqbjwv2drm1w7qyyqzvw8g-guix-extra-source'
exporting path `/gnu/store/0szskn0spa0gkf36p9fkrl9b4r7x67vc-guix-extra-builder'
exporting path `/gnu/store/vg4zq88aw4y1skaljyd092yricg0krj0-guix-extra.drv'
exporting path `/gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv'
exporting path `/gnu/store/7ymrcgnz6v4x1krljh60za1fx0wz57ny-libgit2-0.28.4'
exporting path `/gnu/store/1hapil0ym1k3cii3j95pmabgnxi7c9m0-guile3.0-git-0.3.0'
exporting path `/gnu/store/32569wrdn5wfq864iz889fv3hrz0a35c-guix-extra'
exporting path `/gnu/store/bgwcdqnrb3zqs91hgm4vsxprqmnxb6z0-guix-core'
exporting path `/gnu/store/gdkb4vs4i1pbaifihdnkgvw3bklcdafq-config.scm'
exporting path `/gnu/store/grfziyz24rkbal06ba8kb6d47zhv5m8i-guix-core-source'
offloading '/gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv' to '10.42.0.199'...
offloading build of /gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv to '10.42.0.199'
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
@ build-started /gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv - x86_64-linux /var/log/guix/drvs/5z//hgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv.bz2 12591
[546/546] compiling...  100.0% of 273 files
@ build-succeeded /gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv -
retrieving 1 store item from '10.42.0.199'...
importing file or directory '/gnu/store/60yrpv6cfzl9pzw4sgawfw0b8bx679js-guix-packages-base'...
found valid signature for '/gnu/store/60yrpv6cfzl9pzw4sgawfw0b8bx679js-guix-packages-base'
done with offloaded '/gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv'
successfully built /gnu/store/5zhgzvnyswm8g50aha95rvdx6dpmw329-guix-packages-base.drv
building /gnu/store/7ih7cmbhz1p7a4m7yrgy0s2jawqc666n-guix-packages-base-modules.drv...
process 5174 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.24 (normalized: 2.24)
waiting for locks or build slots...
successfully built /gnu/store/7ih7cmbhz1p7a4m7yrgy0s2jawqc666n-guix-packages-base-modules.drv
process 5174 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 1.97 (normalized: 1.97)
building /gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv...
sending 4 store items (5 MiB) to '10.42.0.199'...
exporting path `/gnu/store/37ljzr1akxh64fbwf7rhn5qdsxs62zh5-guix-packages-builder'
exporting path `/gnu/store/qymkn55sgl7ln68cmkp60xx4h6kckg7p-guix-packages-source'
exporting path `/gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv'
offloading '/gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv' to '10.42.0.199'...
offloading build of /gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv to '10.42.0.199'
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
@ build-started /gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv - x86_64-linux /var/log/guix/drvs/il//y3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv.bz2 12691
[422/422] compiling...  100.0% of 211 files
@ build-succeeded /gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv -
retrieving 1 store item from '10.42.0.199'...
importing file or directory '/gnu/store/d5bz30n1r7fg8xybqip2prrxmfy07jz1-guix-packages'...
found valid signature for '/gnu/store/d5bz30n1r7fg8xybqip2prrxmfy07jz1-guix-packages'
done with offloaded '/gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv'
successfully built /gnu/store/ily3pqqvfkjz5622fxz6mxg31jbiqb21-guix-packages.drv
building /gnu/store/rhk9cknm5wbk30slzzrr52app8mfn4a2-guix-packages-modules.drv...
process 5205 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.73 (normalized: 2.73)
waiting for locks or build slots...
successfully built /gnu/store/rhk9cknm5wbk30slzzrr52app8mfn4a2-guix-packages-modules.drv
process 5205 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.52 (normalized: 2.52)
process 5205 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.31 (normalized: 2.31)
process 5205 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.13 (normalized: 2.13)
process 5205 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 1.96 (normalized: 1.96)
building /gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv...
sending 4 store items (2 MiB) to '10.42.0.199'...
exporting path `/gnu/store/c5f1649rxrhfdb5vfr4s6i7yb4yqhidr-guix-system-source'
exporting path `/gnu/store/nw9kr3wkgfks44wrf8zw9y0l50bnzg77-guix-system-builder'
exporting path `/gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv'
offloading '/gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv' to '10.42.0.199'...
offloading build of /gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv to '10.42.0.199'
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
@ build-started /gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv - x86_64-linux /var/log/guix/drvs/if//qlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv.bz2 12805
[156/156] compiling...  100.0% of 78 files
@ build-succeeded /gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv -
retrieving 1 store item from '10.42.0.199'...
importing file or directory '/gnu/store/6swg1fk14gw145ihh0ml1549cdqvq9n1-guix-system'...
found valid signature for '/gnu/store/6swg1fk14gw145ihh0ml1549cdqvq9n1-guix-system'
done with offloaded '/gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv'
successfully built /gnu/store/ifqlhiq9mlbcq7cy05r2da7yr2c03whl-guix-system.drv
process 5266 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 3.05 (normalized: 3.05)
building /gnu/store/z3mzdfm2x2jrab7g3yhcg06lrgpq2ijz-guix-system-modules.drv...
waiting for locks or build slots...
successfully built /gnu/store/z3mzdfm2x2jrab7g3yhcg06lrgpq2ijz-guix-system-modules.drv
process 5266 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.81 (normalized: 2.81)
process 5266 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.58 (normalized: 2.58)
process 5266 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.37 (normalized: 2.37)
process 5266 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.18 (normalized: 2.18)
process 5266 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.01 (normalized: 2.01)
process 5266 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 1.85 (normalized: 1.85)
building /gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv...
sending 4 store items (1 MiB) to '10.42.0.199'...
exporting path `/gnu/store/nlrwldyvnmbih5qzcv8xhby5jcnnr5gn-guix-cli-source'
exporting path `/gnu/store/z8dgrdv8vqxwn2p8480q6x5fwiyc9f0q-guix-cli-builder'
exporting path `/gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv'
offloading '/gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv' to '10.42.0.199'...
offloading build of /gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv to '10.42.0.199'
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
@ build-started /gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv - x86_64-linux /var/log/guix/drvs/6m//dpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv.bz2 12943
[106/106] compiling...  100.0% of 53 files
@ build-succeeded /gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv -
retrieving 1 store item from '10.42.0.199'...
importing file or directory '/gnu/store/7gh81jn54ak2qw3ahq4nb9dc0zzn0h4v-guix-cli'...
found valid signature for '/gnu/store/7gh81jn54ak2qw3ahq4nb9dc0zzn0h4v-guix-cli'
done with offloaded '/gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv'
successfully built /gnu/store/6mdpdsflpz3axdlifw7mqfdmzhnpzvvc-guix-cli.drv
building /gnu/store/ybxk6d3bccnz52d2s55gcang7795cy3l-guix-cli-modules.drv...
process 5300 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.28 (normalized: 2.28)
waiting for locks or build slots...
successfully built /gnu/store/ybxk6d3bccnz52d2s55gcang7795cy3l-guix-cli-modules.drv
process 5300 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 2.1 (normalized: 2.1)
process 5300 acquired build slot '/var/guix/offload/10.42.0.199:22/0'
load on machine '10.42.0.199' is 1.93 (normalized: 1.93)
building /gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv...
sending 4 store items (0 MiB) to '10.42.0.199'...
exporting path `/gnu/store/k4vp8f9prcfc29lqmzpygrsx8qxmmzs3-guix-system-tests-builder'
exporting path `/gnu/store/sbrl1022yphyzdcjilpabfgq102rxxkc-guix-system-tests-source'
exporting path `/gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv'
offloading '/gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv' to '10.42.0.199'...
offloading build of /gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv to '10.42.0.199'
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
@ build-started /gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv - x86_64-linux /var/log/guix/drvs/fw//r4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv.bz2 13042
[  5/ 46] loading...     21.7% of 23 filesrandom seed for tests: 1582005862
[ 46/ 46] compiling...  100.0% of 23 files
@ build-succeeded /gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv -
retrieving 1 store item from '10.42.0.199'...
importing file or directory '/gnu/store/c98xnkcbm1bd3j69k08kr3d8msm5zg94-guix-system-tests'...
found valid signature for '/gnu/store/c98xnkcbm1bd3j69k08kr3d8msm5zg94-guix-system-tests'
done with offloaded '/gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv'
successfully built /gnu/store/fwr4jlsgxjxkiqn6l4dr1hfl684irmp0-guix-system-tests.drv
building /gnu/store/ysr4d2bqhs4c4viwyk9pvcjcnwv4pnr8-guix-system-tests-modules.drv...
successfully built /gnu/store/ysr4d2bqhs4c4viwyk9pvcjcnwv4pnr8-guix-system-tests-modules.drv
building /gnu/store/mx5kd00k1axs9xrgwn5hibiidbxshy3g-guix-000000000-modules.drv...
successfully built /gnu/store/mx5kd00k1axs9xrgwn5hibiidbxshy3g-guix-000000000-modules.drv
building /gnu/store/flii6im368mj1mlwb1xmnvwhibll0acg-guix-module-union.drv...
successfully built /gnu/store/flii6im368mj1mlwb1xmnvwhibll0acg-guix-module-union.drv
building /gnu/store/cjzvm56h61zhwd56g1ksi91spq567b4b-guix-command.drv...
successfully built /gnu/store/cjzvm56h61zhwd56g1ksi91spq567b4b-guix-command.drv
building /gnu/store/65dva2y1zq173i93z57xzffn34rmfbgw-guix-daemon.drv...
successfully built /gnu/store/65dva2y1zq173i93z57xzffn34rmfbgw-guix-daemon.drv
building /gnu/store/hb87zw934jkgxwkgbbfykwaq55p6pzlq-guix-000000000.drv...
successfully built /gnu/store/hb87zw934jkgxwkgbbfykwaq55p6pzlq-guix-000000000.drv
building CA certificate bundle...
successfully built /gnu/store/qpcnvr43c5rl6bgpsj7l3m38r6xndz7j-ca-certificate-bundle.drv
building fonts directory...
successfully built /gnu/store/scm0rsny7n5kmryffp081hdh6rh2659l-fonts-dir.drv
building directory of Info manuals...
successfully built /gnu/store/qc53qlnzwxlhlm01fxp45ppdnrzw0lfz-info-dir.drv
building database for manual pages...
Creating manual page database...
[  1/  1] building list of man-db entries...
0 entries processed in 0.0 s
successfully built /gnu/store/8k7vn4fbwqvlmhsv604v7zkgils5j0f4-manual-database.drv
building /gnu/store/2hd5a6klgq8zz22rsm3jd4wqw6cbcmbq-profile.drv...
successfully built /gnu/store/2hd5a6klgq8zz22rsm3jd4wqw6cbcmbq-profile.drv
building /gnu/store/zdqspx48gmwa9xv2ibn993qfswq9zgkf-inferior-script.scm.drv...
successfully built /gnu/store/zdqspx48gmwa9xv2ibn993qfswq9zgkf-inferior-script.scm.drv
building package cache...
(repl-version 0 0)
Generating package cache for '/gnu/store/lxl90crn49lgnmxd13ljka6w6dz6vm9p-profile'...
(values (value "/gnu/store/ckyfrrsk8fdx9lzkiwvf0a3p79ll2gfg-guix-package-cache/lib/guix/package.cache"))
successfully built /gnu/store/841rih0j6iskwdxvay7cm94l3vn4idl7-guix-package-cache.drv
building /gnu/store/3rqfd301xgwlaacwppswdxshlc13ky7p-profile.drv...
successfully built /gnu/store/3rqfd301xgwlaacwppswdxshlc13ky7p-profile.drv
building CA certificate bundle...
successfully built /gnu/store/44wi6c2lq0mpkmx940wsi56fmxr8fjh4-ca-certificate-bundle.drv
building fonts directory...
successfully built /gnu/store/1li6nkn0p7zikf5y36ljir2n53rf81cg-fonts-dir.drv
building directory of Info manuals...
successfully built /gnu/store/d80j7mvj59m6h33m3c72mwfckb9xrn7r-info-dir.drv
building database for manual pages...
Creating manual page database...
[ 45/ 45] building list of man-db entries...
1039 entries processed in 3.2 s
successfully built /gnu/store/x1cfgs17hpiw33fpq8gj51ldykf8wd25-manual-database.drv
building /gnu/store/5688khnjjabnh8bnn4hc41j05h1larh9-shepherd-guix-daemon.scm.drv...
successfully built /gnu/store/5688khnjjabnh8bnn4hc41j05h1larh9-shepherd-guix-daemon.scm.drv
building /gnu/store/a2dl48yn635qqbga72gwkqnypd45lxaf-profile.drv...

warning: collision encountered:
  /gnu/store/zg26g1i42sfn26ll4k5i3wb20zmwmpah-info-dir/share/info/dir
  /gnu/store/ma7ccwpzsypkxp88j2jlr4vq1gad06vd-profile/share/info/dir
warning: choosing /gnu/store/zg26g1i42sfn26ll4k5i3wb20zmwmpah-info-dir/share/info/dir

warning: collision encountered:
  /gnu/store/5al8wjz7522q8rqzyfmz46mlbzm70jzj-manual-database/share/man/index.db
  /gnu/store/ma7ccwpzsypkxp88j2jlr4vq1gad06vd-profile/share/man/index.db
warning: choosing /gnu/store/5al8wjz7522q8rqzyfmz46mlbzm70jzj-manual-database/share/man/index.db
successfully built /gnu/store/a2dl48yn635qqbga72gwkqnypd45lxaf-profile.drv
building /gnu/store/7wkb1al9lxp5k84k9b1i5v7h69x9p3wr-shepherd-guix-daemon.go.drv...
successfully built /gnu/store/7wkb1al9lxp5k84k9b1i5v7h69x9p3wr-shepherd-guix-daemon.go.drv
building /gnu/store/jp62bqlvch38sqcqkxk3ddwih84qz8ka-shepherd.conf.drv...
successfully built /gnu/store/jp62bqlvch38sqcqkxk3ddwih84qz8ka-shepherd.conf.drv
building /gnu/store/ixk9m5hqwj42kdzh88vwy06alk9bw811-boot.drv...
successfully built /gnu/store/ixk9m5hqwj42kdzh88vwy06alk9bw811-boot.drv
building /gnu/store/1kmbdnkdip0xbdi4h09jj44nccmpmxh6-system.drv...
successfully built /gnu/store/1kmbdnkdip0xbdi4h09jj44nccmpmxh6-system.drv
/gnu/store/mv1c4cv6c1wws712zi4wz8l6ab8gwn85-system
--8<---------------cut here---------------end--------------->8---

real    58m19.825s
user    3m42.533s
sys     0m1.936s

I've left the full log because it did most poorly, at nearly an hour.

Next I'll try to verify if this long build is triggered amongst the
commits of this change set.

Maxim