Re: [linux-lvm] XFS and LVM

Re: [linux-lvm] XFS and LVM

[Alvaro Garcia Barcena]

	I was wondering if anyone else out there is using XFS with LVM?

Yup. Now what? ;)

Regards, Alvaro

Re: [linux-lvm] XFS and LVM

[Glenn Shannon]

Alvaro Garcia Barcena wrote:

> 	I was wondering if anyone else out there is using XFS with LVM?
> 
> Yup. Now what? ;)
> 
> Regards, Alvaro
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> 
> 
Just looking mainly for tips/tricks/possible headaches.... got any? :)

Glenn

RE: [linux-lvm] XFS and LVM

[Steve Wray]

Oh yeah heres one to do with xfs;
you can't shrink them so watch out.

Mind you, reiserfs is supposed to be shrinkable but,
ahem, it didn't work...

> -----Original Message-----
> From: linux-lvm-admin@sistina.com [mailto:linux-lvm-admin@sistina.com]On
> Behalf Of Glenn Shannon
> Sent: Tuesday, May 22, 2001 12:22 AM
> To: linux-lvm@sistina.com
> Subject: Re: [linux-lvm] XFS and LVM
> 
> 
> Alvaro Garcia Barcena wrote:
> 
> > 	I was wondering if anyone else out there is using XFS with LVM?
> > 
> > Yup. Now what? ;)
> > 
> > Regards, Alvaro
> > _______________________________________________
> > linux-lvm mailing list
> > linux-lvm@sistina.com
> > http://lists.sistina.com/mailman/listinfo/linux-lvm
> > 
> > 
> Just looking mainly for tips/tricks/possible headaches.... got any? :)
> 
> Glenn
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> 

Re: [linux-lvm] XFS and LVM

[Terje Kvernes]

"Steve Wray" <steve.wray@the.net.nz> writes:

> Mind you, reiserfs is supposed to be shrinkable but, ahem, it didn't
> work...
  
  ouch. what happened?

-- 
Terje

RE: [linux-lvm] XFS and LVM

[Steve Wray]

> From: linux-lvm-admin@sistina.com [mailto:linux-lvm-admin@sistina.com]On
> 
> "Steve Wray" <steve.wray@the.net.nz> writes:
> 
> > Mind you, reiserfs is supposed to be shrinkable but, ahem, it didn't
> > work...
>   
>   ouch. what happened?

It wouldn't mount afterward... It was only on /usr/local
whuch was backed up.

Re: [linux-lvm] XFS and LVM

[Ragnar Kjørstad]

On Wed, May 23, 2001 at 10:50:27AM +1200, Steve Wray wrote:
> > From: linux-lvm-admin@sistina.com [mailto:linux-lvm-admin@sistina.com]On
> > 
> > "Steve Wray" <steve.wray@the.net.nz> writes:
> > 
> > > Mind you, reiserfs is supposed to be shrinkable but, ahem, it didn't
> > > work...
> >   
> >   ouch. what happened?
> 
> It wouldn't mount afterward... It was only on /usr/local
> whuch was backed up.

Did you report it to reiserfs-list@namesys.com?


-- 
Ragnar Kj�rstad
Big Storage

RE: [linux-lvm] XFS and LVM

[Steve Wray]

> From: linux-lvm-admin@sistina.com [mailto:linux-lvm-admin@sistina.com]On
> Behalf Of Ragnar Kj�rstad
> On Wed, May 23, 2001 at 10:50:27AM +1200, Steve Wray wrote:
> > > > Mind you, reiserfs is supposed to be shrinkable but, ahem, it didn't
> > > > work...
> > >
> > >   ouch. what happened?
> >
> > It wouldn't mount afterward... It was only on /usr/local
> > whuch was backed up.
>
> Did you report it to reiserfs-list@namesys.com?

nooo, I'm not really using reiserfs in a serious way.
I only tried it out because XFS isn't shrinkable,
so I wondered how reiserfs would perform on a shrink.

I'm going to try ext3 sometime soon...

Re: [linux-lvm] XFS and LVM

[Harald Milz]

In article <20010523010640.C2933@vestdata.no>, Ragnar Kjørstad <lvm@ragnark.vestdata.no> wrote:
>> 
>> It wouldn't mount afterward... It was only on /usr/local
>> whuch was backed up.

> Did you report it to reiserfs-list@namesys.com?

That doesn't always help. I once had a ~1 meg file in the reiserfs root
filesystem which wouldn't delete but I laways got a nice oops. I reported
it to Hans and got a reply that someone would look at it bit that never
actually happened (at least got no feedback).

But that was just once. I still have everything on reiserfs on LVM on my
machines, and just started to experiment with XFS. The fact that it is not
shrinkable is a bit annoying though. Like AIX JFS. ... 

-- 
Harald Milz           |     hm@linux-magazin.de     | If one studies too
Linux Magazin         | phone  +49 (0) 89 993411-20 | zealously, one easily
Stefan-George-Ring 24 | fax    +49 (0) 89 993411-99 | loses his pants. --
D-81929 Muenchen      | http://www.linux-magazin.de | A. Einstein.

How about ext3? (was RE: [linux-lvm] XFS and LVM)

[Steve Wray]

Any experience with ext3?
Is it shrinkable?


> -----Original Message-----
> From: linux-lvm-admin@sistina.com [mailto:linux-lvm-admin@sistina.com]On
> Behalf Of Harald Milz
> Sent: Wednesday, May 23, 2001 8:35 PM
> To: linux-lvm@sistina.com
> Subject: Re: [linux-lvm] XFS and LVM
>
>
> In article <20010523010640.C2933@vestdata.no>, Ragnar Kj�rstad
> <lvm@ragnark.vestdata.no> wrote:
> >>
> >> It wouldn't mount afterward... It was only on /usr/local
> >> whuch was backed up.
>
> > Did you report it to reiserfs-list@namesys.com?
>
> That doesn't always help. I once had a ~1 meg file in the reiserfs root
> filesystem which wouldn't delete but I laways got a nice oops. I reported
> it to Hans and got a reply that someone would look at it bit that never
> actually happened (at least got no feedback).
>
> But that was just once. I still have everything on reiserfs on LVM on my
> machines, and just started to experiment with XFS. The fact that it is not
> shrinkable is a bit annoying though. Like AIX JFS. ...
>
> --
> Harald Milz           |     hm@linux-magazin.de     | If one studies too
> Linux Magazin         | phone  +49 (0) 89 993411-20 | zealously,
> one easily
> Stefan-George-Ring 24 | fax    +49 (0) 89 993411-99 | loses his pants. --
> D-81929 Muenchen      | http://www.linux-magazin.de | A. Einstein.
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
>

Re: How about ext3? (was RE: [linux-lvm] XFS and LVM)

[Stephen C. Tweedie]

Hi,

On Wed, May 23, 2001 at 08:35:36PM +1200, Steve Wray wrote:
> Any experience with ext3?
> Is it shrinkable?

It is format-compatible with ext2, so offline e2resize should work
happily on ext3 for both shrinking and growing.  Online, only growing
has been implemented (but not all of the kernel support is
integrated).

I haven't tried doing a resize on ext3 so we might have to teach the
e2resize tools not to worry if they see the HAS_JOURNAL flag set in
the superblock, but there is nothing in the format itself to prevent
it from working.

Cheers,
 Stephen

Re: [linux-lvm] XFS and LVM

[Steve Lord]

> But that was just once. I still have everything on reiserfs on LVM on my
> machines, and just started to experiment with XFS. The fact that it is not
> shrinkable is a bit annoying though. Like AIX JFS. ...
> 
> --
> Harald Milz           |     hm@linux-magazin.de     | If one studies too

Growing is a fairly simple operation for filesystems, shrinking complexity
is a function of metadata complexity, and XFS metadata is very complex,
the exception to this is the case of filesystems designed with shrinking
in mind, but they will almost certainly have to make compromises to support
this.

Shrinking is also a less used operation in production situations than growing,
it might be fun to play with, but the type of system XFS comes from you would
tend to just buy more disks than move one out of an existing filesystem.
The only really useful 'shrink' operation in this scenario is remove a
failing drive, and given the volume managers which usually sit under XFS
the only thing capable of doing this is mirroring the drive (or using
hardware raid).

Oh, and online shrinking would be the preferable implementation in a
production situation, which means doing it with transactions.

So these are the reasons XFS does not have a shrink capability. As a
technical option it is possible to implement this, but the code would
be very complex and we have a lot of other things to do which have a
higher priority. As I have said before, if someone wants to try it
I would be happy to offer suggestions.

Steve

Re: How about ext3? (was RE: [linux-lvm] XFS and LVM)

[Jay Weber]

Yes, it is shrinkable.  It performs the same as ext2 other than the fact
it has journaling for the most part. :)

Snapshotting is a bit different at present.  You can snapshot just fine if
you umount the filesystem first, since that leaves the filesystem in a
clean state.  If you want to do online snapshotting you'll have to add in
a hook to ext3 to use the LVM_VFS_ENHANCEMENT fsync_dev_lockfs() and
unlockfs() features.  The recent ext3 0.0.6b does support a journal
barrier feature so you can flush the journal and set the fs to a clean
state during the snapshot.  I've a dated patch here somewhere, I'll dig
around for it.  The problem the above resolves is that snapshotting an
active ext3 filesystem means there's a journal with bits of data hanging
about that needs to be addressed prior to the snapshot.  If it's not you
won't be able to mount the snapshot since they are read-only and the
journal would not be able to replay.

There is also online resizing available to some degree for ext2/ext3.
Andreas Dilger maintains that if I'm correct, I haven't messed with it
much myself yet. :)

On Wed, 23 May 2001, Steve Wray wrote:

> Date: Wed, 23 May 2001 20:35:36 +1200
> From: Steve Wray <steve.wray@the.net.nz>
> Reply-To: linux-lvm@sistina.com
> To: linux-lvm@sistina.com
> Subject: How about ext3? (was RE: [linux-lvm] XFS and LVM)
>
> Any experience with ext3?
> Is it shrinkable?
>
>
> > -----Original Message-----
> > From: linux-lvm-admin@sistina.com [mailto:linux-lvm-admin@sistina.com]On
> > Behalf Of Harald Milz
> > Sent: Wednesday, May 23, 2001 8:35 PM
> > To: linux-lvm@sistina.com
> > Subject: Re: [linux-lvm] XFS and LVM
> >
> >
> > In article <20010523010640.C2933@vestdata.no>, Ragnar Kjørstad
> > <lvm@ragnark.vestdata.no> wrote:
> > >>
> > >> It wouldn't mount afterward... It was only on /usr/local
> > >> whuch was backed up.
> >
> > > Did you report it to reiserfs-list@namesys.com?
> >
> > That doesn't always help. I once had a ~1 meg file in the reiserfs root
> > filesystem which wouldn't delete but I laways got a nice oops. I reported
> > it to Hans and got a reply that someone would look at it bit that never
> > actually happened (at least got no feedback).
> >
> > But that was just once. I still have everything on reiserfs on LVM on my
> > machines, and just started to experiment with XFS. The fact that it is not
> > shrinkable is a bit annoying though. Like AIX JFS. ...
> >
> > --
> > Harald Milz           |     hm@linux-magazin.de     | If one studies too
> > Linux Magazin         | phone  +49 (0) 89 993411-20 | zealously,
> > one easily
> > Stefan-George-Ring 24 | fax    +49 (0) 89 993411-99 | loses his pants. --
> > D-81929 Muenchen      | http://www.linux-magazin.de | A. Einstein.
> > _______________________________________________
> > linux-lvm mailing list
> > linux-lvm@sistina.com
> > http://lists.sistina.com/mailman/listinfo/linux-lvm
> >
>
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
>

Re: [linux-lvm] XFS and LVM

[Harald Milz]

In article <200105231113.f4NBDLA21032@jen.americas.sgi.com>, Steve Lord <lord@sgi.com> wrote:

> Shrinking is also a less used operation in production situations than growing,

This what IBM marketing as well always told me (when I was an IBMer) but it
turned out over time that I don't always buy a new disk when I need more
space, but try to clean up some leftovers and resize my partitioning. Then
it's nice if you can shrink. I mean you can always backup a filesystem,
delete it, create it smaller, and restore the backup. But that is
cumbersome and requires more scheduled downtime than desirable. 

Does SGI have plans to eventually implement shrinking, or am I left with
the every so often heard marketing statement that I sure don't need it? 

(SCNR)

-- 
Harald Milz           |     hm@linux-magazin.de     | "Our vision is to speed
Linux Magazin         | phone  +49 (0) 89 993411-20 | up time, eventually
Stefan-George-Ring 24 | fax    +49 (0) 89 993411-99 | eliminating it." --
D-81929 Muenchen      | http://www.linux-magazin.de | Alex Schure

Re: How about ext3? (was RE: [linux-lvm] XFS and LVM)

[Thierry Mallard]

On Wed, May 23, 2001 at 10:34:32AM +0100, Stephen C. Tweedie wrote:
> Hi,
> 
> On Wed, May 23, 2001 at 08:35:36PM +1200, Steve Wray wrote:
> > Any experience with ext3?
> > Is it shrinkable?
> 
[...]

Just curious, but I was told that ext3 wasn't supported on linux 2.4.. is this
true ?

-- 
Thierry Mallard                    | GnuPG key on pgp.ai.mit.edu
http://IDEALX.com                  | key 0xA3D021CB
http://thierry.mallard.com         | 

Re: [linux-lvm] XFS and LVM

[Andreas Dilger]

Steve Wray writes:
> nooo, I'm not really using reiserfs in a serious way.
> I only tried it out because XFS isn't shrinkable,
> so I wondered how reiserfs would perform on a shrink.
> 
> I'm going to try ext3 sometime soon...

Just FYI, I have patches/tools to do online and offline resizing of ext2,
and have an alpha online ext3 resizer.  The ext2 code is pretty solid.
You can grow an ext2 filesystem online, but you need to unmount it to
shrink the filesystem.

Cheers, Andreas
-- 
Andreas Dilger  \ "If a man ate a pound of pasta and a pound of antipasto,
                 \  would they cancel out, leaving him still hungry?"
http://www-mddsp.enel.ucalgary.ca/People/adilger/               -- Dogbert

Re: [linux-lvm] XFS and LVM

[Steve Lord]

> In article <200105231113.f4NBDLA21032@jen.americas.sgi.com>, Steve Lord <lord
> @sgi.com> wrote:
> 
> > Shrinking is also a less used operation in production situations than growi
> ng,
> 
> This what IBM marketing as well always told me (when I was an IBMer) but it
> turned out over time that I don't always buy a new disk when I need more
> space, but try to clean up some leftovers and resize my partitioning. Then
> it's nice if you can shrink. I mean you can always backup a filesystem,
> delete it, create it smaller, and restore the backup. But that is
> cumbersome and requires more scheduled downtime than desirable. 
> 
> Does SGI have plans to eventually implement shrinking, or am I left with
> the every so often heard marketing statement that I sure don't need it? 

Well, when it comes to working for a company which is supposed to be making
money, you cannot just go and implement features which will burn maybe
$75,000 to get going correctly (that includes dealing with support calls
etc from the customers who find bugs, fixing the bugs etc), unless there
is a return on the investment.

So I think the answer is no, we will not be doing it in the forseeable
future. But if some large customer was to wave several million in orders
at us with this as a requirement it might be a different matter.

Steve

> 
> (SCNR)
> 
> -- 
> Harald Milz           |     hm@linux-magazin.de     | "Our vision is to speed
> Linux Magazin         | phone  +49 (0) 89 993411-20 | up time, eventually
> Stefan-George-Ring 24 | fax    +49 (0) 89 993411-99 | eliminating it." --
> D-81929 Muenchen      | http://www.linux-magazin.de | Alex Schure
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> 

Re: How about ext3? (was RE: [linux-lvm] XFS and LVM)

[Andreas Dilger]

Stephen writes:
> On Wed, May 23, 2001 at 08:35:36PM +1200, Steve Wray wrote:
> > Any experience with ext3?
> > Is it shrinkable?
> 
> It is format-compatible with ext2, so offline e2resize should work
> happily on ext3 for both shrinking and growing.  Online, only growing
> has been implemented (but not all of the kernel support is
> integrated).
> 
> I haven't tried doing a resize on ext3 so we might have to teach the
> e2resize tools not to worry if they see the HAS_JOURNAL flag set in
> the superblock, but there is nothing in the format itself to prevent
> it from working.

The ext2resize code has no problem with the non-reserved journal files
for offline resizing.  However, I just noticed last night that it doesn't
handle the reserved journal inode properly.  It halts the resize because
it can't find the owner of the blocks that the reserved journal is using.

Also, while I have finished an online ext3 resizing patch which works
with the journaling properly, I haven't polished it up and finished the
user-space support for it.  It is available on request to people who
really want to play with it...

Cheers, Andreas
-- 
Andreas Dilger  \ "If a man ate a pound of pasta and a pound of antipasto,
                 \  would they cancel out, leaving him still hungry?"
http://www-mddsp.enel.ucalgary.ca/People/adilger/               -- Dogbert

Re: How about ext3? (was RE: [linux-lvm] XFS and LVM)

[Andreas Dilger]

Thierry Mallard writes:
> Just curious, but I was told that ext3 wasn't supported on linux 2.4..
> is this true ?

It _was_ true a few weeks ago, but ext3 has now been ported to 2.4.
Please see archives at http://marc.theaimsgroup.com/?l=ext2-devel&r=1&w=4
for details on how to get the code, and the current status.  It is
already relatively stable, but has not recieved a lot of testing.

Cheers, Andreas
-- 
Andreas Dilger  \ "If a man ate a pound of pasta and a pound of antipasto,
                 \  would they cancel out, leaving him still hungry?"
http://www-mddsp.enel.ucalgary.ca/People/adilger/               -- Dogbert

Re: How about ext3? (was RE: [linux-lvm] XFS and LVM)

[Jay Weber]

Send it my way.  I'm game. :)  I haven't checked out any of your online
resize at all up to this point, I've been using the resize2fs (Ted Tso)
bit for offline resizing, but I'm more than willing to bang on the online
support also. :)

On Wed, 23 May 2001, Andreas Dilger wrote:

> Date: Wed, 23 May 2001 10:53:28 -0600 (MDT)
> From: Andreas Dilger <adilger@turbolinux.com>
> Reply-To: linux-lvm@sistina.com
> To: linux-lvm@sistina.com
> Cc: Stephen Tweedie <sct@redhat.com>, Steve Wray <steve.wray@the.net.nz>
> Subject: Re: How about ext3? (was RE: [linux-lvm] XFS and LVM)
>
> Stephen writes:
> > On Wed, May 23, 2001 at 08:35:36PM +1200, Steve Wray wrote:
> > > Any experience with ext3?
> > > Is it shrinkable?
> >
> > It is format-compatible with ext2, so offline e2resize should work
> > happily on ext3 for both shrinking and growing.  Online, only growing
> > has been implemented (but not all of the kernel support is
> > integrated).
> >
> > I haven't tried doing a resize on ext3 so we might have to teach the
> > e2resize tools not to worry if they see the HAS_JOURNAL flag set in
> > the superblock, but there is nothing in the format itself to prevent
> > it from working.
>
> The ext2resize code has no problem with the non-reserved journal files
> for offline resizing.  However, I just noticed last night that it doesn't
> handle the reserved journal inode properly.  It halts the resize because
> it can't find the owner of the blocks that the reserved journal is using.
>
> Also, while I have finished an online ext3 resizing patch which works
> with the journaling properly, I haven't polished it up and finished the
> user-space support for it.  It is available on request to people who
> really want to play with it...
>
> Cheers, Andreas
> --
> Andreas Dilger  \ "If a man ate a pound of pasta and a pound of antipasto,
>                  \  would they cancel out, leaving him still hungry?"
> http://www-mddsp.enel.ucalgary.ca/People/adilger/               -- Dogbert
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html
>