unofficial mirror of guix-devel@gnu.org 
 help / color / mirror / code / Atom feed
* Treating tests as special case
@ 2018-04-05  5:24 Pjotr Prins
  2018-04-05  6:05 ` Gábor Boskovits
                   ` (3 more replies)
  0 siblings, 4 replies; 22+ messages in thread
From: Pjotr Prins @ 2018-04-05  5:24 UTC (permalink / raw)
  To: guix-devel

Last night I was watching Rich Hickey's on Specs and deployment. It is
a very interesting talk in many ways, recommended. He talks about
tests at 1:02 into the talk:

  https://www.youtube.com/watch?v=oyLBGkS5ICk

and he gave me a new insight which rang immediately true. He said:
what is the point of running tests everywhere? If two people test the
same thing, what is the added value of that? (I paraphrase)

With Guix a reproducibly building package generates the same Hash on
all dependencies. Running the same tests every time on that makes no
sense.

And this hooks in with my main peeve about building from source. The
building takes long enough. Testing takes incredibly long with many
packages (especially language related) and are usually single core
(unlike the build). It is also bad for our carbon foot print. Assuming
everyone uses Guix on the planet, is that where we want to end up?

Burning down the house.

Like we pull substitutes we could pull a list of hashes of test cases
that are known to work (on Hydra or elsewhere). This is much lighter
than storing substitutes, so when the binaries get removed we can
still retain the test hashes and have fast builds. Also true for guix
repo itself.

I know there are two 'inputs' I am not accounting for: (1) hardware
variants and (2) the Linux kernel. But, honestly, I do not think we
are in the business of testing those. We can assume these work. If
not, any issues will be found in other ways (typically a segfault ;).
Our tests are generally meaningless when it comes to (1) and (2). And
packages that build differently on different platforms, like openblas,
we should opt out on. 

I think this would be a cool innovation (in more ways than one).

Pj.

^ permalink raw reply	[flat|nested] 22+ messages in thread

end of thread, other threads:[~2018-04-06 18:37 UTC | newest]

Thread overview: 22+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-04-05  5:24 Treating tests as special case Pjotr Prins
2018-04-05  6:05 ` Gábor Boskovits
2018-04-05  8:39   ` Pjotr Prins
2018-04-05  8:58     ` Hartmut Goebel
2018-04-05  6:21 ` Björn Höfling
2018-04-05  8:43   ` Pjotr Prins
2018-04-06  8:58     ` Chris Marusich
2018-04-06 18:36       ` David Pirotte
2018-04-05 10:14   ` Ricardo Wurmus
2018-04-05 12:19     ` Björn Höfling
2018-04-05 14:10       ` Ricardo Wurmus
2018-04-05 10:26 ` Ricardo Wurmus
2018-04-05 14:14   ` Ludovic Courtès
2018-04-05 14:59     ` Pjotr Prins
2018-04-05 15:17       ` Ricardo Wurmus
2018-04-05 15:24       ` Ludovic Courtès
2018-04-05 16:41         ` Pjotr Prins
2018-04-05 18:35           ` Pjotr Prins
2018-04-06  7:57           ` Retaining substitutes Ludovic Courtès
2018-04-05 20:26 ` Treating tests as special case Mark H Weaver
2018-04-06  6:06   ` Pjotr Prins
2018-04-06  8:27     ` Ricardo Wurmus

Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/guix.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).