Re: mkfs+mount failure of small fs on ppc64

On 9/13/16 4:44 PM, Eric Sandeen wrote: > on ppc64, 4.7-rc kernel, git btrfs-progs, v4.7.2: > > # truncate --size=500m testfile > # ./mkfs.btrfs testfile > # mkdir -p mnt > # mount -o loop testfile mnt Same failure on aarch64 if that makes it any more interesting. ;) # mount -o loop testfile

mkfs+mount failure of small fs on ppc64

on ppc64, 4.7-rc kernel, git btrfs-progs, v4.7.2: # truncate --size=500m testfile # ./mkfs.btrfs testfile # mkdir -p mnt # mount -o loop testfile mnt btrfs-progs v4.7.2 See http://btrfs.wiki.kernel.org for more information. Label: (null) UUID:

Re: Small fs

Chris Murphy posted on Mon, 12 Sep 2016 08:48:49 -0600 as excerpted: > On Sun, Sep 11, 2016 at 10:54 PM, Duncan <1i5t5.dun...@cox.net> wrote: > >> On the bright side, the double-whammy of being under such tight >> filesystem size constraints, coupled with finding out you have less >> than half

Re: Small fs

On 12 September 2016 at 19:55, Austin S. Hemmelgarn wrote: > I'm not sure about gparted, but the default behavior for mkfs is as follows: > 1. Is the device rotational? (check /sys/block//rotational). If > not, do some extra stuff to try and ID it as an SSD. If it is an

Re: Small fs

. And third party tools (ex: gparted) plays with it. Let's warn users with some documentation, together with "A formal small fs" behaviour.. I'm not sure about gparted, but the default behavior for mkfs is as follows: 1. Is the device rotational? (check /sys/block//rotational). If no

Re: Small fs

tools (ex: gparted) plays with it. Let's warn users with some documentation, together with "A formal small fs" behaviour.. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

Re: Small fs

> btrfs filesystem df /mnt/back/boot > Data, single: total=8.00MiB, used=0.00B > System, DUP: total=8.00MiB, used=16.00KiB > Metadata, DUP: total=32.00MiB, used=112.00KiB > GlobalReserve, single: total=16.00MiB, used=0.00B > IT IS DUP!! Wait wait wait a second: This is 256 MB SINGLE created by

Re: Small fs

On 2016-09-12 10:51, Chris Murphy wrote: On Mon, Sep 12, 2016 at 8:09 AM, Henk Slager wrote: FWIW, I use BTRFS for /boot, but it's not for snapshotting or even the COW, it's for DUP mode and the error recovery it provides. Most people don't think about this if it hasn't

Re: Small fs

On Mon, Sep 12, 2016 at 8:09 AM, Henk Slager wrote: >> FWIW, I use BTRFS for /boot, but it's not for snapshotting or even the COW, >> it's for DUP mode and the error recovery it provides. Most people don't >> think about this if it hasn't happened to them, but if you get a bad

Re: Small fs

On Sun, Sep 11, 2016 at 10:54 PM, Duncan <1i5t5.dun...@cox.net> wrote: > On the bright side, the double-whammy of being under such tight > filesystem size constraints, coupled with finding out you have less than > half the space of the filesystem actually available due to default-mixed- > mode

Re: Small fs

On 2016-09-12 10:09, Henk Slager wrote: FWIW, I use BTRFS for /boot, but it's not for snapshotting or even the COW, it's for DUP mode and the error recovery it provides. Most people don't think about this if it hasn't happened to them, but if you get a bad read from /boot when loading the

Re: Small fs

> FWIW, I use BTRFS for /boot, but it's not for snapshotting or even the COW, > it's for DUP mode and the error recovery it provides. Most people don't > think about this if it hasn't happened to them, but if you get a bad read > from /boot when loading the kernel or initrd, it can essentially

Re: Small fs

>> Just to note again: >> Ordinary 127MB btrfs gives "Out of space" around 64MB payload. 128MB is >> usable to the end. > Thanks, and just to clarify for others possibly following along or > googling it up later, that's single mode (as opposed to dup mode) for at > least data, if in normal

Re: Small fs

On 2016-09-12 08:54, Imran Geriskovan wrote: On 9/11/16, Chris Murphy wrote: Something else that's screwy in that bug that I just realized, why is it not defaulting to mixed-block groups on a 100MiB fallocated file? I thought mixed-bg was the default below a certain

Re: Small fs

On 9/11/16, Chris Murphy wrote: > Something else that's screwy in that bug that I just realized, why is > it not defaulting to mixed-block groups on a 100MiB fallocated file? I > thought mixed-bg was the default below a certain size like 2GiB or > whatever? >> With an

Re: Small fs

On 2016-09-11 15:51, Martin Steigerwald wrote: Am Sonntag, 11. September 2016, 19:46:32 CEST schrieb Hugo Mills: On Sun, Sep 11, 2016 at 09:13:28PM +0200, Martin Steigerwald wrote: Am Sonntag, 11. September 2016, 16:44:23 CEST schrieb Duncan: * Metadata, and thus mixed-bg, defaults to DUP

Re: Small fs

On 2016-09-11 15:21, Martin Steigerwald wrote: Am Sonntag, 11. September 2016, 21:56:07 CEST schrieb Imran Geriskovan: On 9/11/16, Duncan <1i5t5.dun...@cox.net> wrote: Martin Steigerwald posted on Sun, 11 Sep 2016 17:32:44 +0200 as excerpted: What is the smallest recommended fs size for

Re: Small fs

Chris Murphy posted on Sun, 11 Sep 2016 21:03:04 -0600 as excerpted: > The man page says: > "The recommended size for the mixed mode is for filesystems less than > 1GiB." But in this case recommended !=default which requires some mental > gymnastics to rectify. If mixed-bg becomes obsolete upon

Re: Small fs

Imran Geriskovan posted on Sun, 11 Sep 2016 21:56:07 +0300 as excerpted: > On 9/11/16, Duncan <1i5t5.dun...@cox.net> wrote: >> Martin Steigerwald posted on Sun, 11 Sep 2016 17:32:44 +0200 as >> excerpted: What is the smallest recommended fs size for btrfs? Can we say size should be in

Re: Small fs

On Sun, Sep 11, 2016 at 8:00 PM, Duncan <1i5t5.dun...@cox.net> wrote: > Chris Murphy posted on Sun, 11 Sep 2016 14:33:18 -0600 as excerpted: > >> Something else that's screwy in that bug that I just realized, why is it >> not defaulting to mixed-block groups on a 100MiB fallocated file? I >>

Re: Small fs

Chris Murphy posted on Sun, 11 Sep 2016 14:33:18 -0600 as excerpted: > Something else that's screwy in that bug that I just realized, why is it > not defaulting to mixed-block groups on a 100MiB fallocated file? I > thought mixed-bg was the default below a certain size like 2GiB or > whatever?

Re: Small fs

On Sun, Sep 11, 2016 at 9:27 AM, Imran Geriskovan wrote: > What is the smallest recommended fs size for btrfs? It depends on the layout. And there is some confusion about the mkfs command message it returns when it doesn't work out.

Re: Small fs

Am Sonntag, 11. September 2016, 19:46:32 CEST schrieb Hugo Mills: > On Sun, Sep 11, 2016 at 09:13:28PM +0200, Martin Steigerwald wrote: > > Am Sonntag, 11. September 2016, 16:44:23 CEST schrieb Duncan: > > > * Metadata, and thus mixed-bg, defaults to DUP mode on a single-device > > > filesystem

Re: Small fs

On Sun, Sep 11, 2016 at 09:13:28PM +0200, Martin Steigerwald wrote: > Am Sonntag, 11. September 2016, 16:44:23 CEST schrieb Duncan: > > * Metadata, and thus mixed-bg, defaults to DUP mode on a single-device > > filesystem (except on ssd where I actually still use it myself, and > > recommend it

Re: Small fs

Am Sonntag, 11. September 2016, 21:56:07 CEST schrieb Imran Geriskovan: > On 9/11/16, Duncan <1i5t5.dun...@cox.net> wrote: > > Martin Steigerwald posted on Sun, 11 Sep 2016 17:32:44 +0200 as excerpted: > >>> What is the smallest recommended fs size for btrfs? > >>> Can we say size should be in

Re: Small fs

Am Sonntag, 11. September 2016, 16:44:23 CEST schrieb Duncan: > * Metadata, and thus mixed-bg, defaults to DUP mode on a single-device > filesystem (except on ssd where I actually still use it myself, and > recommend it except for ssds that do firmware dedupe). In mixed-mode > this means two

Re: Small fs

On 9/11/16, Duncan <1i5t5.dun...@cox.net> wrote: > Martin Steigerwald posted on Sun, 11 Sep 2016 17:32:44 +0200 as excerpted: >>> What is the smallest recommended fs size for btrfs? >>> Can we say size should be in multiples of 64MB? >> Do you want to know the smalled *recommended* or the smallest

Re: Small fs

Martin Steigerwald posted on Sun, 11 Sep 2016 17:32:44 +0200 as excerpted: > Am Sonntag, 11. September 2016, 18:27:30 CEST schrieben Sie: >> What is the smallest recommended fs size for btrfs? >> >> - There are mentions of 256MB around the net. >> - Gparted reserves minimum of 256MB for btrfs.

Re: Small fs

Am Sonntag, 11. September 2016, 18:27:30 CEST schrieben Sie: > What is the smallest recommended fs size for btrfs? > > - There are mentions of 256MB around the net. > - Gparted reserves minimum of 256MB for btrfs. > > With an ordinary partition on a single disk, > fs created with just

Small fs

What is the smallest recommended fs size for btrfs? - There are mentions of 256MB around the net. - Gparted reserves minimum of 256MB for btrfs. With an ordinary partition on a single disk, fs created with just "mkfs.btrfs /dev/sdxx": - 128MB works fine. - 127MB works but as if it is 64MB. Can