My Windows build is much slower than Linux build. Any way to speed up?

[Michael Meeks]

Hi Jeff,

On Mon, 2013-12-23 at 20:10 +0800, Jeff Cai wrote:
> I am new to LibreOffice. Recently, I downloaded the code and started
> my build. At first, I built under Linux, which simply "git", apt-get
> those library, autogen and make. It worked like a charm.

	Good :-)
> 
> Then I switched to Windows build. I noticed that it builds more things
> than Linux build does(Like unit test). And it's much SLOWER!

	Linux builds the same unit test, but they run headless so you just
don't see them :-) Also the unit tests on Windows are more valuable
since there are many fewer developers there.
> 
> Is there any way to speed up windows build ?

	You can disable link time optimisation with a configure option, that
probably helps quite a bit, and of course you can turn off debugging
symbols - that may also help - though both clearly have costs for
debugging / runtime performance.

>  I used precompiled header in my autogen.sh, I also use the "correct"
> make(3.82) from libreoffice build tool, and set parallels parameter to
> 4(make -j 4).

	Yep - the state of the cygwin build & MSVC compiler is really rather
appalling there, clearly even working out what is wrong with MSVC is
hard. Kohei had some data point around the new templates in the string
header taking a long time to compile: I wonder whether we could make
those Linux-only, and use a 'const char *' constructor on Windows (which
may speed things up).

> Any way to disable the build of unit tests? I've searched through the
> help to autgen, and found nothing.

	There is but it's deliberately hard to find ;-) it's not good for the
health of your build.

	If you are doing an incremental build; it's far better to do eg.

	'make sc'

	to just re-build calc.

	HTH,

		Michael.

-- 
 michael.meeks at collabora.com  <><, Pseudo Engineer, itinerant idiot