Re: Compilation speed

[Lars Ingebrigtsen <larsi@gnus.org>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> 00:00:50 Loading emacs-lisp/byte-run (source)...
>> 00:00:50 Loading emacs-lisp/backquote (source)...
>> [...]
>> 00:01:02 Dump complete
>>
>> And dumping takes 12 seconds.
>
> For re-builds, this is also a very significant chunk, especially since
> we often do it twice.

Yes, that's true.

>> This seems to proceed in parallell until we reach:
>>
>> 00:01:17   INFO     Scraping files for loaddefs.el... 
>> [...]
>> 00:01:54   INFO     Scraping files for loaddefs.el...done
>>
>> Which is single-threaded and takes a whopping 37 seconds!  Could that
>> possibly be parallelised in some way?
>
> IIRC this should be generated in parallel with the compilation of the
> preloaded files.  Not sure why it's not the case.

On my laptop (which is much slower), the loaddefs generation often runs
in parallel with other things (well, sort of -- it's usually completed
about a quarter of what it's doing when make runs out of other things to
schedule).

> Note that the native-compiler should solve a significant part of this
> problem (by increasing the amount of time spent compiling the .elc files
> in parallel ;-)

:-)

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no