Re: Maximum file system size of XFS?

Martin Steigerwald
2013-03-11T22:04:20Z

Am Montag, 11. März 2013 schrieb Martin Steigerwald:
> Am Montag, 11. März 2013 schrieb Martin Steigerwald:
> > Am Montag, 11. März 2013 schrieb Martin Steigerwald:
> > > 2) Create a insanely big sparse file
> > >
> > > merkaba:~> truncate -s1E /mnt/zeit/evenmorecrazy.img
> > > merkaba:~> ls -lh /mnt/zeit/evenmorecrazy.img
> > > -rw-r--r-- 1 root root 1,0E Mär 11 22:37 /mnt/zeit/evenmorecrazy.img
> > >
> > > (No, this won´t work with Ext4.)
> >
> > Okay, you can´t go beyond 8 EiB for a single file which is about what I
>
> > have read somewhere:
> […]
>
> > merkaba:/mnt/zeit> truncate -s7E /mnt/zeit/evenmorecrazy.img
> > merkaba:/mnt/zeit> LANG=C truncate -s8E /mnt/zeit/evenmorecrazy.img
> > truncate: invalid number '8E': Value too large for defined data type
> > merkaba:/mnt/zeit#1> ls -lh
> > insgesamt 0
> > -rw-r--r-- 1 root root 7,0E Mär 11 22:49 evenmorecrazy.img
> >
> > So so tests stops there, until you concatenate two of those files with
> > LVM or SoftRAID 0 (if that works). Like this (I just had to try it):
> >
> >
> > merkaba:/mnt/zeit> ls -lh
> > insgesamt 0
> > -rw-r--r-- 1 root root 7,0E Mär 11 22:49 evenmorecrazy.img
> > -rw-r--r-- 1 root root 7,0E Mär 11 22:52 evenmorecrazy.img2
> > merkaba:/mnt/zeit> losetup /dev/loop0 evenmorecrazy.img
> > merkaba:/mnt/zeit> losetup /dev/loop1 evenmorecrazy.img2
> >
> > merkaba:/mnt/zeit#5> pvcreate /dev/loop0
> >
> > Physical volume "/dev/loop0" successfully created
> >
> > merkaba:/mnt/zeit> pvcreate /dev/loop1
> >
> > Physical volume "/dev/loop1" successfully created
> >
> > merkaba:/mnt/zeit> vgcreate justinsane /dev/loop0 /dev/loop1
> >
> > PV /dev/loop0 too large for extent size 4,00 MiB.
> > Format-specific setup of physical volume '/dev/loop0' failed.
> > Unable to add physical volume '/dev/loop0' to volume group
> >
> > 'justinsane'.
>
> […]
>
> > merkaba:/mnt/zeit#5> vgcreate --physicalextentsize 4G justinsane
> > /dev/loop0 /dev/loop1
> >
> > Volume group "justinsane" successfully created
> >
> > merkaba:/mnt/zeit> vgs
> >
> > VG #PV #LV #SN Attr VSize VFree
> > justinsane 2 0 0 wz--n- 14,00e 14,00e
> > merkaba 1 4 0 wz--n- 278,99g 4,85g
> >
> > merkaba:/mnt/zeit>
> >
> > merkaba:/mnt/zeit> vgdisplay justinsane
>
> […]
>
> > Enough insanity for today :)
>
> Not quite:
> > I won´t mkfs.xfs on it, the 20 GiB of the just filesystem wouldn´t be
> > enough.
>
> Ok, there seems to be another limit involved:
>
> merkaba:/mnt/zeit> lvcreate -n yourbiggiexfs -L14E justinsane
> Volume group "justinsane" has insufficient free space (3758096382
> extents): 3758096384 required.
[…]
> merkaba:/mnt/zeit#5> LANG=C lvcreate -n yourbiggiexfs -L13E justinsane
> /dev/justinsane/yourbiggiexfs: lseek 0 failed: Invalid argument
> /dev/justinsane/yourbiggiexfs: lseek 0 failed: Invalid argument
> Logical volume "yourbiggiexfs" created
> merkaba:/mnt/zeit> LANG=C lvs
> /dev/justinsane/yourbiggiexfs: lseek 14987979559888945152 failed:
> Invalid argument
> /dev/justinsane/yourbiggiexfs: lseek 14987979559889002496 failed:
> Invalid argument

Well,

merkaba:/mnt/zeit> LANG=C ls -l
total 24
-rw-r--r-- 1 root root 8070450532247928832 Mar 11 23:02 evenmorecrazy.img
-rw-r--r-- 1 root root 8070450532247928832 Mar 11 23:02 evenmorecrazy.img2

looks crazy enough for me already.

(Ok, I really stop this now :)

Thanks,
--
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7