How safe is ZFS to use for a home user?

Gary Jennejohn gary.jennejohn at
Sat Dec 22 07:38:40 PST 2007

On Fri, 21 Dec 2007 22:34:07 -0500
"John Klimek" <jklimek at> wrote:

> Has anybody ever lost data due to any bugs or anything like that?  I'm
> going to use this ZFS as my primary storage medium (and poor man's
> backup solution), so I would be devastated if I lost my entire array
> due to a bug or other issue (aside from losing two hard drives in a
> three hard drive RAID-Z array).

I lost a mirror on 2 SATA drives when I installed a new mobo. A plain
ZFS concatenation of 2 partitions on a SCSI drive didn't get lost. I've
never lost data due to a crash.

Might have been pilot error. Might have had something to do with the
way the new mobo assigned the disks. Luckily I had a backup of the
really important stuff.

> Also, my system is going to have 3x 400 GB (RAID-Z) and 1x 80 GB
> (Standalone ZFS) and has 1.5 GB RAM (P3-1.0 GHz).
> What should I be setting my kmem and kmem_max to (or whatever) to
> avoid this bug I keep hearing about?

This sort of question has been answered umpteen times already. Check
out the ML archive or the wiki (

Gary Jennejohn

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