Re: [PATCH] doc: ensure sphinx output is reproducible

[Bruce Richardson <bruce.richardson@intel.com>]

On Mon, Nov 27, 2023 at 05:45:52PM +0100, Thomas Monjalon wrote:
> 06/07/2023 14:49, Christian Ehrhardt:
> > On Mon, Jul 3, 2023 at 5:29 PM Thomas Monjalon <thomas@monjalon.net> wrote:
> > >
> > > 29/06/2023 14:58, christian.ehrhardt@canonical.com:
> > > > From: Christian Ehrhardt <christian.ehrhardt@canonical.com>
> > > >
> > > > By adding -j we build in parallel, to make building on multiprocessor
> > > > machines more effective. While that works it does also break
> > > > reproducible builds as the order of the sphinx generated searchindex.js
> > > > is depending on execution speed of the individual processes.
> > > [...]
> > > > -if Version(ver) >= Version('1.7'):
> > > > -    sphinx_cmd += ['-j', 'auto']
> > >
> > > What is the impact on build speed on an average machine?
> > 
> > Hi,
> > I haven't tested this in isolation as it was just a mandatory change
> > on the Debian/Ubuntu side.
> > And the time for exactly and only the doc build is hidden inside the
> > concurrency of meson.
> > But I can compare a full build [1] and a full build with the change [2].
> > 
> > That is an average build machine and it is 35 seconds slower with the
> > change to no more do doc builds in parallel.
> 
> I would prefer adding an option for reproducible build
> (which is not a common requirement).
> 
Taking a slightly different tack, is it possible to sort the searchindex.js
file post-build, so that even reproducible builds get the benefits of
parallelism?

/Bruce