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

[Christian Lohmaier]

Hi *,

On Mon, Dec 23, 2013 at 2:09 PM, Michael Meeks
<michael.meeks at collabora.com> wrote:
> On Mon, 2013-12-23 at 20:10 +0800, Jeff Cai wrote:
>> [Windows build much slower than on linux]
> [...]
>>  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).

You shouldn't need tomanually set -j4 on the commandline, configure
will set it to the number of processors/cores.

>         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.

It's not so much about the compiler (at least not all of it). But esp.
when you build with additional languages, then the
build-system-wrapper stuff is what seriously impacts build performance
on windows.

Just compare

mkdir foo ; cd foo
time touch {1..1000}

with

mkdir foo; cd foo
time for i in {1..1000}; do touch $i ; done

While on linux there's no real difference, on windows this is more
than an order of magnitude...(and the build system does the equivalent
of the latter a lot)

Of course windows cannot make (reliable) use of ccache - and
definitely not in combination with precompiled headers, so that's
where the compiler comes into play..

ciao
Christian