Asserts enabled with new-build cause performance regression

[alanz]

Testing new-configure times against https://github.com/alanz/haskell-ide-engine master (165b98d6be0d248b735033219b7e67b84539e062)

With a standard ~/cabal/config, generated by cabal 1.24.0.0. from hackage, and with the following security setup, with secure: False

repository hackage.haskell.org
  url: http://hackage.haskell.org/
  secure: False
  -- secure: True
  -- root-keys:
  root-keys: 
     fe331502606802feac15e514d9b9ea83fee8b6ffef71335479a2e68d84adc6b0,
     1ea9ba32c526d1cc91ab5e5bd364ec5e9e8cb67179a471872f6e26f0ae773d42,
     2c6c3627bd6c982990239487f1abd02e08a02e6cf16edb105a8012d444d870c3,
     0a5c7ea47cd1b15f01f5f51a33adda7e655bc0f0b0615baa8e271f4c3351e21d,
     51f0161b906011b52c6613376b1ae937670da69322113a246a09f807c62f6921

  -- key-threshold:
  key-threshold: 3

I have

Repeat

rm -fr dist-newstlye
cabal new-configure

Until there are no downloads

Then

rm -fr dist-newstyle
time cabal new-configure

This gives a plan, and says

real    0m5.924s
user    0m5.684s
sys 0m0.248s

Then, using current master (bb2026c), and flipping
secure: True,

cabal-1.25 update
rm -fr dist-newstyle
cabal-1.25 new-configure

Once things stabilise

rm -fr dist-newstyle
time cabal-1.25 new-configure

Gives

real    0m21.058s
user    0m20.852s
sys 0m0.188s

[alanz]

I just set secure: False, and did

cabal-1.25 update
rm -fr dist-newstyle
cabal-1.25 new-configure
# Downloads a bunch of stuff
rm -fr dist-newstyle
time cabal-1.25 new-configure

And I get

real    0m20.788s
user    0m20.596s
sys 0m0.180s

So the security stuff does not seem to make an appreciable difference

[alanz]

alanz@alanz-laptop:~/mysrc/github/haskell/cabal$ git bisect good
6f1c370165829faa917deb6f8213960cfac79a23 is the first bad commit
commit 6f1c370165829faa917deb6f8213960cfac79a23
Author: Duncan Coutts <duncan@community.haskell.org>
Date:   Fri Sep 9 22:39:14 2016 +0100

    Experiment with using -fno-ignore-asserts in more places

    Always in the tests, and also for devs in the cabal.project

:040000 040000 8fde9a0bac89c7c132ab56b349d0aacbe6e0352b 5580aa41f6f44da9df3e0cadddbe9887d6afb5db M  cabal-install
:100644 100644 b5ba5deb8b4ab19305d083b0fc631a646153a450 ee26b6d20fb01cc69649c2029cda5d4e14168afe M  cabal.project

alanz@alanz-laptop:~/mysrc/github/haskell/cabal$ git bisect log
git bisect start
# bad: [bb2026c4dd6238338cfbcc4a34e3fa1f6868dc13] Make `Version` type opaque (#3905)
git bisect bad bb2026c4dd6238338cfbcc4a34e3fa1f6868dc13
# good: [e884c63b6c19616ee0e777341e0320106c882b61] Update release date to May
git bisect good e884c63b6c19616ee0e777341e0320106c882b61
# skip: [715ce276e9ce33c72e32da45974a249365c460c7] Merge pull request #3180 from grayjay/conditional-tests
git bisect skip 715ce276e9ce33c72e32da45974a249365c460c7
# good: [5c0934651f0d2df659abfb5c073a1a4f2cdd4877] Correct gen-script on osx
git bisect good 5c0934651f0d2df659abfb5c073a1a4f2cdd4877
# good: [4779e6fd1df92c100b1e39ab343ecb0a89571bcd] Add unit tests for 'WeightedPSQ'.
git bisect good 4779e6fd1df92c100b1e39ab343ecb0a89571bcd
# good: [42411899c710af01b477c26a5b2b9c90a56f2d2b] Fix highlighting in all docs
git bisect good 42411899c710af01b477c26a5b2b9c90a56f2d2b
# bad: [7399850e79534d24847cc86bac8ba2b2132c7856] Clarify the differences with the GetOpt from base
git bisect bad 7399850e79534d24847cc86bac8ba2b2132c7856
# good: [240900ddf366bd8fab43a9b4f2c489a4fb1f24aa] Add examples to help text for reconfigure command
git bisect good 240900ddf366bd8fab43a9b4f2c489a4fb1f24aa
# bad: [48d9077bffa894e63e0ba3969a37af64b9e010f9] Merge pull request #3866 from Ericson2314/patch-1
git bisect bad 48d9077bffa894e63e0ba3969a37af64b9e010f9
# good: [f0b9ea77e66474e3801481c440e504b20313a5ae] Merge pull request #3855 from ttuegel/reconfigure
git bisect good f0b9ea77e66474e3801481c440e504b20313a5ae
# bad: [6f1c370165829faa917deb6f8213960cfac79a23] Experiment with using -fno-ignore-asserts in more places
git bisect bad 6f1c370165829faa917deb6f8213960cfac79a23
# good: [34cc46ffbdfabe30442d8053c6a2ab587276289a] Add the plumbing for cabal new-build --only-dependencies
git bisect good 34cc46ffbdfabe30442d8053c6a2ab587276289a
# good: [9f6f844940deea3d2ed889367341eddc3088164a] Correct the spelling of dependencies in multiple places
git bisect good 9f6f844940deea3d2ed889367341eddc3088164a
# first bad commit: [6f1c370165829faa917deb6f8213960cfac79a23] Experiment with using -fno-ignore-asserts in more places

[hvr]

Especially this one here in cabal.project is evil:

program-options
  -- So us hackers get all the assertion failures early:
  ghc-options: -fno-ignore-asserts

as it applies to all of cabal's deps

[ezyang]

@alanz With @hvr's commit did the performance go back to something reasonable?

[alanz]

Yes

[ezyang]

OK, I'll go ahead and close this.