Re: [gentoo-dev] News Item: Portage rsync hardlink support

["Michał Górny" <mgorny@gentoo.org>]

Dnia 8 lipca 2018 09:14:06 CEST, Zac Medico <zmedico@gentoo.org> napisał(a):
>On 07/07/2018 11:53 PM, Michał Górny wrote:
>> Dnia 8 lipca 2018 08:08:31 CEST, Zac Medico <zmedico@gentoo.org>
>napisał(a):
>>> Please review.
>>>
>>> Title: Portage rsync hardlink support
>>> Author: Zac Medico <zmedico@gentoo.org>
>>> Posted: 2018-07-11
>>> Revision: 1
>>> News-Item-Format: 2.0
>>> Display-If-Installed: sys-apps/portage
>>>
>>> For users of the rsync tree, beginning with sys-apps/portage-2.3.42,
>>> the default behavior for sync operations will use hardlinks in order
>>> to ensure that a repository remains in a valid state if something
>>> goes wrong [1]. For example, if signature verification fails during
>a
>>> sync operation, the new hardlink behavior will preserve the previous
>>> state of the repository.
>>>
>>> The new behavior may conflict with configurations that restrict the
>>> use of hardlinks, such as overlay filesystems. Therefore, users will
>>> have to set "sync-allow-hardlinks = no" in repos.conf if they have
>>> a configuration that restricts the use of hardlinks, but this should
>>> not be very common:
>>>
>>> [DEFAULT]
>>> sync-allow-hardlinks = no
>>>
>>> [1] https://bugs.gentoo.org/660410 sys-apps/portage: use rsync
>>>    --link-dest to implement atomic repository updates (and abort if
>>>    signature verification fails)
>> 
>> Is safe git syncing implemented already? If not, maybe finish it
>first and cover both with a single news item. Git is going to be more
>efficient here, so people may want to learn they have an alternative.
>
>Yeah there's already a patch for git sync [1] but I'd rather not make
>this news item more complicated than it needs to be. I wouldn't have
>bothered with a news item except that I want to give people some
>warning
>in case they are using overlayfs [2]. I think the efficiency difference
>between rsync and git here are pretty negligible for most people.

Are you sure about that? That might have been the case so far but this hardlink tree may actually tip the balance.

>
>[1] https://bugs.gentoo.org/660372
>[2]
>https://www.brunsware.de/blog/gentoo/portage-tree-squashfs-overlayfs.html


-- 
Best regards,
Michał Górny (by phone)