[buildd-tools-devel] Bug#710073: Bug#710073: Bug#710073: sbuild: add copy-on-write support

[Roger Leigh]

On Fri, Jul 05, 2013 at 10:15:07AM -0700, Geoffrey Thomas wrote:
> On Fri, 5 Jul 2013, Roger Leigh wrote:
> 
> >I would suspect that we can make it use overlayfs using the same
> >infrastructure--it'll just need teaching about the new filesystem
> >type.
> 
> Hasn't overlayfs support been in schroot since 1.5.2-1 (May 2012)? I
> don't think any more support is needed on the sbuild side. Ubuntu
> seems to be making active use of overlayfs chroots -- mk-sbuild from
> ubuntu-dev-tools 0.136 (November 2011) onwards makes them, and they
> carry no patches to schroot and no relevant patches to sbuild.

Yes, you're correct, I'd forgotten it was already added--it's not
a feature I use myself very often.

> By the way, regarding cowdancer and LD_PRELOAD, I semi-recently
> learned about fakeroot-ng, which implements fakeroot using ptrace
> instead of LD_PRELOAD and is therefore more reliable. I wonder if
> the same approach could be applied to cowdancer. (I've long wanted a
> "fakeschroot" that doesn't require elevated privilege in order to
> build things....)

If such a thing is possible, that would be very interesting.  I
don't think I'll have time to look at it myself in the near
future, but I'd certainly support any work on it.  Removing all
need for root privileges for sbuild would be a great achievement;
I'd certainly be happy to remove the need for root in the build
chroot.


Regards,
Roger

-- 
  .''`.  Roger Leigh
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