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planetf1
23rd March 2010, 07:50 AM
When I initially installed F12 on a new laptop I opted for btrfs. I've since upgraded to F13 alpha. Rather than my usual use of LVM with multiple filesystems for /opt /home etc I went for a single partition (and an ext3 /boot + paging partition)

btrfs has been entirely stable, but my attempts to experiment with some of the features have been underwhelming -- for example in the tools being not quite there yet such as snapshot deletion.

I have a new HDD arriving in next few days (larger) so will need to either (from a live cd/usb)
* Do a regular clone/fdisk to expand & carry on working
* Do a file-level copy

I'm now thinking of the latter, and going back to my old style, which throws up a few questions

* Am I incorrectly asserting that btrfs tools aren't there yet?
* Is "find . -print | cpio -pdm" or "cp -R" appropriate for the copy -- any recommended parms
* Is there much additional overhead of LVM compared with btrfs. (assume not)
* What's "best practice" these days on a single user laptop - multiple or single filesystems, lvm?
* Or for the sake of the community should I continue with btrfs - after all someone has to ensure it continues to get the exposure/testing it needs.....

Hummph. After that I think perhaps the last point is ringing out to me....

RahulSundaram
23rd March 2010, 09:20 AM
Hi,

It is still considered experimental in Fedora and upstream for good reasons however at this point, if you have a solid backup of your data, you might as well as continue the ride and provide the feedback for the pain points to be improved.

RahulSundaram
23rd March 2010, 09:20 AM
Hi,

It is still considered experimental in Fedora and upstream for good reasons however at this point, if you have a solid backup of your data, you might as well as continue the ride and provide the feedback for the pain points to be improved.

SlowJet
23rd March 2010, 10:34 AM
I jsut answer a strange LVM problem so I'll add some more LVM enlightenment here while I'm at it.

LVM and brtfs have no comparison elements.
LVM overhead is very little and only occurs when issing LVM commands.
The referencing of file systems and LVM meta data is very lite, a bit more for raid LV's.
BTRfS on the other hand has lots of overhead as it is designed to run with multiple volumes and take checksums on meta and data on two volumes making it very stable (when finished).
ext3, ext4, brts are file systems, and without write barriers on they can all get whacked if the timing is just right.
That timing is very small for a desktop.

SJ

jvillain
24th March 2010, 02:30 AM
My understanding is if you did a conversion from ext4 to btrfs and you want to convert back to ext4 all you have to do is mount your ext4 directory assuming you haven't deleted it.

SlowJet
24th March 2010, 03:06 AM
https://btrfs.wiki.kernel.org/index.php/Conversion_from_Ext3

btrfs can be rolled back to the origin ext3/4 but the btrfs data is gone.

SJ

AdamW
24th March 2010, 08:39 PM
btrfs-tools is available in Fedora, however due to a bug in anaconda it wasn't getting automatically installed when you create a btrfs partition in the installer (we've just squashed that bug recently). So you'd have to yum it.

Milena
28th March 2010, 03:44 AM
just a quick question about the current state of btrfs in fedora, is the on-disk format already in its final version or might it be necessary to re-format all btrfs partitions once it has become default in fedora ?

Firewing1
28th March 2010, 04:11 AM
If you opt for file-level copy, I would go for rsync instead of cp -R since it supports transfer progress as well as preserving ACLs and a bunch of other stuff:
rsync -ruh --progress -t -o -g -X -A -p -l
That copies recursively, updating only older files so you can stop the transfer half-way if you need to and start right from where you left off. --progress and -h enable progress reports with human-readable output (using MB, GB instead of everything in bytes) and the -t -o -g <...> preserves times, permissions, ownership, ACLs, XTTRS and symlinks.

SlowJet
28th March 2010, 05:01 AM
just a quick question about the current state of btrfs in fedora, is the on-disk format already in its final version or might it be necessary to re-format all btrfs partitions once it has become default in fedora ?

No one knows the answer to that as brtfs has a way to go before it is going to be a usable f/s.
The format could change.

SJ

jvillain
29th March 2010, 01:03 AM
just a quick question about the current state of btrfs in fedora, is the on-disk format already in its final version or might it be necessary to re-format all btrfs partitions once it has become default in fedora ?


I read some where that the structure will stay the same now so no more wiping and starting again.

hephasteus
31st March 2010, 12:09 AM
btrfs would likely be great for allowing package maintainers that don't have a lot of experience to get some good experience more easily, by allowing them to make mistakes without hampering the users/testers as much. But you have to remember fedora's tactics. If they can't get people to test something enough they make it default. :D
I think btrfs has enough going for it that it won't be made default for a long long time. Probably could have used it more last year than this year and next though.