Re: 2 PB filesystem ok?

Ulli Horlacher
2024-05-01T18:19:07Z

On Wed 2024-05-01 (16:16), Tomas Volf wrote:
> On 2024-05-01 10:50:12 +0200, Ulli Horlacher wrote:
>
> > On Mon 2024-04-29 (12:34), Johannes Thumshirn wrote:
> >
> > > I have used 2PB filesystems in my RAID Stripe Tree test environment, but
> > > for practical uses, I suggest you to enable the block-group tree feature
> > > during mkfs time.
> >
> > I cannot find such an option in man-page for mkfs.btrfs
>
> $ mkfs.btrfs -O list-all
> Filesystem features available:
> mixed-bg - mixed data and metadata block groups (compat=2.6.37, safe=2.6.37)
> quota - quota support (qgroups) (compat=3.4)
> extref - increased hardlink limit per file to 65536 (compat=3.7, safe=3.12, default=3.12)
> raid56 - raid56 extended format (compat=3.9)
> skinny-metadata - reduced-size metadata extent refs (compat=3.10, safe=3.18, default=3.18)
> no-holes - no explicit hole extents for files (compat=3.14, safe=4.0, default=5.15)
> free-space-tree - free space tree (space_cache=v2) (compat=4.5, safe=4.9, default=5.15)
> raid1c34 - RAID1 with 3 or 4 copies (compat=5.5)
> zoned - support zoned devices (compat=5.12)
> block-group-tree - block group tree to reduce mount time (compat=6.1)
>
> So I believe it would be `mkfs.btrfs -O block-group-tree ...'.

root@fex:~# mkfs.btrfs -O list-all
Filesystem features available:
mixed-bg - mixed data and metadata block groups (0x4, compat=2.6.37, safe=2.6.37)
extref - increased hardlink limit per file to 65536 (0x40, compat=3.7, safe=3.12, default=3.12)
raid56 - raid56 extended format (0x80, compat=3.9)
skinny-metadata - reduced-size metadata extent refs (0x100, compat=3.10, safe=3.18, default=3.18)
no-holes - no explicit hole extents for files (0x200, compat=3.14, safe=4.0, default=5.15)
raid1c34 - RAID1 with 3 or 4 copies (0x800, compat=5.5)
zoned - support zoned devices (0x1000, compat=5.12)

root@fex:~# btrfs --version
btrfs-progs v5.16.2

This is Ubuntu 22.04

--
Ullrich Horlacher Server und Virtualisierung
Rechenzentrum TIK
Universitaet Stuttgart E-Mail: horlacher@tik.uni-stuttgart.de
Allmandring 30a Tel: ++49-711-68565868
70569 Stuttgart (Germany) WWW: https://www.tik.uni-stuttgart.de/
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