[linux-lvm] is lvmraid 1 thinpool with integrity safe?

[David Teigland]

On Sun, Apr 09, 2023 at 02:21:50PM +0200, Arvid Picciani wrote:
> Hi,
> 
> doing some performance tests i noticed that lvmraid + integrity + thinpool
> outperforms zfs z1 by 5x while offering the same features. (snapshots,
> integrity)
> 
> Is this somehow unsafe or how come it is so unpopular?
> 
> lvcreate --type raid1 --mirrors 1 --size '100M' loop --name loopmeta
> --raidintegritymode journal
> lvcreate --type raid1 --mirrors 1 --size '700M' loop --name loopdata
> --raidintegritymode journal

Hi, that command does not actually enable integrity.  You need to include
the option "--raidintegrity y".  (lvcreate should perhaps warn you about
setting raidintegritymode when you've not enabled integrity.)

> lvconvert --type thin-pool --poolmetadata loop/loopmeta loop/loop

We do not currently permit raid+integrity to be used for a thin pool.  It
should be enabled in a coming release.

Dave