Gentoo Logo
Gentoo Spaceship




Note: Due to technical difficulties, the Archives are currently not up to date. GMANE provides an alternative service for most mailing lists.
c.f. bug 424647
List Archive: gentoo-dev
Navigation:
Lists: gentoo-dev: < Prev By Thread Next > < Prev By Date Next >
Headers:
To: gentoo-dev@g.o
From: Michał Górny <mgorny@g.o>
Subject: Re: Re: proj/portage:master commit in: pym/portage/dbapi/
Date: Sat, 26 Nov 2011 17:08:31 +0100
On Sat, 26 Nov 2011 21:28:51 +0530
Nirbheek Chauhan <nirbheek@g.o> wrote:

> On Sat, Nov 26, 2011 at 8:39 PM, Michał Górny <mgorny@g.o>
> wrote:
> > But in this particular case, I don't think COW is particularly
> > useful. If it works only on filesystem bounds, we could move the
> > file directly anyway.
> >
> 
> There are still a few specific cases in which CoW would indeed be
> useful. IIRC, reflinking of files works across btrfs *subvolumes*, and
> such a copy would normally be detected as a cross-device move.

For such a thing, shouldn't rename() work neat anyway?

> Another use would be an patch-merge which makes use of *ranged
> reflinks* to only CoW copy those parts of the file that were
> changed[1]. rsync has support for this, but only while appending to
> files (--append-verify --no-whole-file).

So, it'd be like:
1) CoW-dup old file,
2) patch-merge into the duped old file,
3) replace.

Am I understanding correctly?

-- 
Best regards,
Michał Górny
Attachment:
signature.asc (PGP signature)
Replies:
Re: Re: proj/portage:master commit in: pym/portage/dbapi/
-- Nirbheek Chauhan
References:
Re: proj/portage:master commit in: pym/portage/dbapi/
-- Fabian Groffen
Re: Re: proj/portage:master commit in: pym/portage/dbapi/
-- Nirbheek Chauhan
Re: proj/portage:master commit in: pym/portage/dbapi/
-- Nirbheek Chauhan
Re: Re: proj/portage:master commit in: pym/portage/dbapi/
-- Ciaran McCreesh
Re: Re: proj/portage:master commit in: pym/portage/dbapi/
-- Rich Freeman
Re: Re: proj/portage:master commit in: pym/portage/dbapi/
-- Michał Górny
Navigation:
Lists: gentoo-dev: < Prev By Thread Next > < Prev By Date Next >
Previous by thread:
Re: Re: proj/portage:master commit in: pym/portage/dbapi/
Next by thread:
Re: Re: proj/portage:master commit in: pym/portage/dbapi/
Previous by date:
Re: Re: proj/portage:master commit in: pym/portage/dbapi/
Next by date:
Re: Re: proj/portage:master commit in: pym/portage/dbapi/


Updated Jun 29, 2012

Summary: Archive of the gentoo-dev mailing list.

Donate to support our development efforts.

Copyright 2001-2013 Gentoo Foundation, Inc. Questions, Comments? Contact us.