zfs discuss - Jul 2010 - core dumps eating space in snapshots

I have many core files stuck in snapshots eating up gigs of my disk space. Most
of these are BE''s which I don''t really want to delete right
now.

Is there a way to get rid of them? I know snapshots are RO but can I do some
magic with clones and reclaim my space?
-- 
This message posted from opensolaris.org

> From: zfs-discuss-bounces at opensolaris.org [mailto:zfs-discuss-
> bounces at opensolaris.org] On Behalf Of devsk
> 
> I have many core files stuck in snapshots eating up gigs of my disk
> space. Most of these are BE''s which I don''t really want
to delete right
> now.
Ok, you don''t want to delete them ...

> Is there a way to get rid of them? I know snapshots are RO but can I do
> some magic with clones and reclaim my space?
You don''t want to delete them, but you don''t want them to take
up space
either?  Um ... Sorry, can''t be done.  Move them to a different disk
...

Or clarify what it is that you want.

If you''re saying you have core files in your present filesystem that
you
don''t want to delete ... And you also have core files in snapshots that
you
*do* want to delete ...  As long as the file hasn''t been changing,
it''s not
consuming space beyond what''s in the current filesystem.  (See the
output of
zfs list, looking at sizes and you''ll see that.)  If it has been
changing
... the cores in snapshot are in fact different from the cores in present
filesytem ... then the only way to delete them is to destroy snapshots.

Or have I still misunderstood the question?

On 27.07.10 14:21, Edward Ned Harvey wrote:
>> From: zfs-discuss-bounces at opensolaris.org [mailto:zfs-discuss-
>> bounces at opensolaris.org] On Behalf Of devsk
>>
>> I have many core files stuck in snapshots eating up gigs of my disk
>> space. Most of these are BE''s which I don''t really
want to delete right
>> now.
>
> Ok, you don''t want to delete them ...
>
>
>> Is there a way to get rid of them? I know snapshots are RO but can I do
>> some magic with clones and reclaim my space?
>
> You don''t want to delete them, but you don''t want them to
take up space
> either?  Um ... Sorry, can''t be done.  Move them to a different
disk ...
>
> Or clarify what it is that you want.
>
> If you''re saying you have core files in your present filesystem
that you
> don''t want to delete ... And you also have core files in snapshots
that you
> *do* want to delete ...  As long as the file hasn''t been changing,
it''s not
> consuming space beyond what''s in the current filesystem.  (See the
output of
> zfs list, looking at sizes and you''ll see that.)  If it has been
changing
> ... the cores in snapshot are in fact different from the cores in present
> filesytem ... then the only way to delete them is to destroy snapshots.
>
> Or have I still misunderstood the question?
yes, I think so.

Here''s how I read it: the snapshots contain lots more than the core
files,
and OP wants to remove only the core files (I''m assuming they
weren''t
discovered before the snapshot was taken) but retain the rest.

does that explain it better?

HTH
Michael
-- 
michael.schuster at oracle.com	http://blogs.sun.com/recursion
Recursion, n.: see ''Recursion''

Thanks, Michael. That''s exactly right.

I think my requirement is: writable snapshots.

And I was wondering if someone knowledgeable here could tell me if I could do
this magically by using clones without creating a tangled mess of branches,
because clones in a way are writable snapshots.
-- 
This message posted from opensolaris.org

> From: zfs-discuss-bounces at opensolaris.org [mailto:zfs-discuss-
> bounces at opensolaris.org] On Behalf Of devsk
> 
> Thanks, Michael. That''s exactly right.
> 
> I think my requirement is: writable snapshots.
> 
> And I was wondering if someone knowledgeable here could tell me if I
> could do this magically by using clones without creating a tangled mess
> of branches, because clones in a way are writable snapshots.
Oh.  If the goal is to reclaim disk space that is consumed by certain files
in snapshots, without destroying the whole snapshot ... Maybe some day, but
for now it''s not possible.  And probably "someday" will never
come.  Because
consensus seems to be that writable snapshots (a) would be really difficult
to implement and (b) seems to go against the moral fibers of the people who
might think about being able to implement it.