[gentoo-user] distcc to compile Gentoo on the laptop

[gentoo-user] distcc to compile Gentoo on the laptop

[Christopher Lemire]

Hello Gentoo users, I have one of the higher end pentium 3s running at 1ghz
on a laptop. I have started to install Gentoo on it. Once Stage 3
(Hardened) and Portage were installed, the first things I installed
were vim and distcc. My desktop is a amd quad core at 2.8 ghz stock.
When I had Gentoo on it once before, compiling went really fast using
MAKEOPT=-j5. My desktop is now running Fedora 16 and it's 64-bit,
LUKS, RAID0. I looked up from the Gentoo Handbook and the Gentoo Wiki
documentation about distcc. It all seems to assume that all the other
computers are also running Gentoo. Also because the desktop is running
64-bit Fedora, and the laptop can only run 32 bit, there is the need
for cross compiling. Here's all the issues I am running into that I'm
asking for help to solve.

1. Both systems are not Gentoo.

2. Fedora has distcc and distccd available in the repos, but both
packages are 64 bit.

3. The need for cross-compiling between architectures. The Gentoo Wiki
says use crossdev. That package is available in the Gentoo
repositories through emerge, but when I checked with my Fedora system,
it was not.

4. According to what I read, gcc version a.b.c where a, b, and c are
numbers, a and b need to be the same on both systems. It is ok for c
to be different. My Gentoo has gcc 4.5.x while Fedora has gcc 4.6.x.

So my question is if this is do-able and if anybody has experience
doing this. I want to do the distcc both for the learning experience
and because just emerging distcc on the laptop alone took at least 2
hours.

Christopher Lemire <christopher.lemire@gmail.com>
Ubuntu 64 bit Linux Raid Level 0

Gnu Privacy Guard Key Fingerprint = 3E1A 9103 EF3D 4885 6866  E9DE
C69F 18B3 E13B 0909

Web: http://linuxinnovations.blogspot.com
Jabber: recursivequicksort@jabber.org

Re: [gentoo-user] distcc to compile Gentoo on the laptop

[Daniel Wagener]

On Wed, 13 Jun 2012 01:04:19 -0500
Christopher Lemire <christopher.lemire@gmail.com> wrote:

> Hello Gentoo users, I have one of the higher end pentium 3s running at 1ghz
> on a laptop. I have started to install Gentoo on it. Once Stage 3
> (Hardened) and Portage were installed, the first things I installed
> were vim and distcc. My desktop is a amd quad core at 2.8 ghz stock.
> When I had Gentoo on it once before, compiling went really fast using
> MAKEOPT=-j5. My desktop is now running Fedora 16 and it's 64-bit,
> LUKS, RAID0. I looked up from the Gentoo Handbook and the Gentoo Wiki
> documentation about distcc. It all seems to assume that all the other
> computers are also running Gentoo. Also because the desktop is running
> 64-bit Fedora, and the laptop can only run 32 bit, there is the need
> for cross compiling. Here's all the issues I am running into that I'm
> asking for help to solve.
> 
> 1. Both systems are not Gentoo.
> 
> 2. Fedora has distcc and distccd available in the repos, but both
> packages are 64 bit.
> 
> 3. The need for cross-compiling between architectures. The Gentoo Wiki
> says use crossdev. That package is available in the Gentoo
> repositories through emerge, but when I checked with my Fedora system,
> it was not.
> 
> 4. According to what I read, gcc version a.b.c where a, b, and c are
> numbers, a and b need to be the same on both systems. It is ok for c
> to be different. My Gentoo has gcc 4.5.x while Fedora has gcc 4.6.x.
> 
> So my question is if this is do-able and if anybody has experience
> doing this. I want to do the distcc both for the learning experience
> and because just emerging distcc on the laptop alone took at least 2
> hours.
> 
> Christopher Lemire <christopher.lemire@gmail.com>
> Ubuntu 64 bit Linux Raid Level 0


What about a different approach: gentoo in a VM on the desktop
Would that not be much easier?
Of course some processor power is used for the VM itself, but it should still significantly decrease compilation time on the laptop.
Plus you can easily equip other machines with that VM and use their power too.

Re: [gentoo-user] distcc to compile Gentoo on the laptop

[Yohan Pereira]

On Wed, Jun 13, 2012 at 08:43:20AM +0200, Daniel Wagener wrote:
> On Wed, 13 Jun 2012 01:04:19 -0500
> 
> What about a different approach: gentoo in a VM on the desktop
> Would that not be much easier?
> Of course some processor power is used for the VM itself, but it should still significantly decrease compilation time on the laptop.
> Plus you can easily equip other machines with that VM and use their power too.
> 
What about a chroot? that would be much lighter compared to a VM.
Alternativly you can use the chroot to build binnary pkgs that can be
installed on the laptop. 

-- 

- Yohan Pereira

The difference between a Miracle and a Fact is exactly the difference
between a mermaid and a seal.
                -- Mark Twain

Re: [gentoo-user] distcc to compile Gentoo on the laptop

[YoYo Siska]

On Thu, Jun 14, 2012 at 01:49:16AM +0530, Yohan Pereira wrote:
> On Wed, Jun 13, 2012 at 08:43:20AM +0200, Daniel Wagener wrote:
> > On Wed, 13 Jun 2012 01:04:19 -0500
> > 
> > What about a different approach: gentoo in a VM on the desktop
> > Would that not be much easier?
> > Of course some processor power is used for the VM itself, but it should still significantly decrease compilation time on the laptop.
> > Plus you can easily equip other machines with that VM and use their power too.
> > 
> What about a chroot? that would be much lighter compared to a VM.
> Alternativly you can use the chroot to build binnary pkgs that can be
> installed on the laptop. 

There are 3 solutions I can think of:

1. Get a cross compiler for i686 working under fedora (have no idea
about that, except manually setuping and compiling gcc) and setup the
Fedora's distcc to use that correctly (this should go more or less
according to the docs on the gentoo wiki regarding cmake and i686 vs
amd64)

2. Create a gentoo chroot on the Fedora OS. Much "lightweight" that a
virtual machine, you can setup the cross toolchain and distcc according
to the wiki, you just have to play a bit with how to start the distcc
inside the chroot (a plain /etc/init.d/distcc start inside the chroot 
won't work). Note that you can run a i686 chroot in an amd64 system, so
you actually don't need to set up any fancy crosscompiler inside the
chroot. Just run the chroot as 'linux32 chroot /mnt/chrooot ...' to make
sure uname and similar get correct info...

3. Mount the laptops root filesystem through nfs on the fast computer
(use no_root_squash on the laptop export to have correct root access to
files) bind-mount something local (disk or tmpfs if you have enough mem)
over /var/tmp/portage, chroot into it (don't forget to mount /proc,
maybe /sys and maybe bind-mount /dev, though that should not be needed
and don't forget 'linux32 chroot') and run emerges there... you will
actually be running everything on the fast computer, only the access to
the laptops disk will be through the network. With a fast network it
should be a lot faster then working ont the slower notebook (note that
if you bind-mount /var/tmp/portage inside the chroot, most of the
compilation will be working with a local disk...) Compared to the distcc
method, even the configure phases will be much faster...  I do this
often with my Pentium M 1.6Ghz thinkpad laptop and my quad core amd64
desktop...



yoyo

> 

Re: [gentoo-user] distcc to compile Gentoo on the laptop

[Thanasis]

on 06/14/2012 02:05 AM YoYo Siska wrote the following:

> 
> 3. Mount the laptops root filesystem through nfs on the fast computer
> (use no_root_squash on the laptop export to have correct root access to
> files) bind-mount something local (disk or tmpfs if you have enough mem)
> over /var/tmp/portage, chroot into it (don't forget to mount /proc,
> maybe /sys and maybe bind-mount /dev, though that should not be needed
> and don't forget 'linux32 chroot') and run emerges there... you will
> actually be running everything on the fast computer, only the access to
> the laptops disk will be through the network. With a fast network it
> should be a lot faster then working ont the slower notebook (note that
> if you bind-mount /var/tmp/portage inside the chroot, most of the
> compilation will be working with a local disk...) Compared to the distcc
> method, even the configure phases will be much faster...  I do this
> often with my Pentium M 1.6Ghz thinkpad laptop and my quad core amd64
> desktop...

Exactly. I do this too.
You also need to pay attention and set CFLAGS correctly and not to "native".
Like:
CFLAGS="-march=pentium3 -O2 -pipe -fomit-frame-pointer"