Using ZFS on FreeBSD 7.0

Preston Hagar prestonh at
Wed Feb 27 23:05:32 UTC 2008

On Wed, Feb 27, 2008 at 4:13 PM, Wojciech Puchar
<wojtek at> wrote:
> > will replace all other FS's -ya all others!!!
>  how sure you are?
I would second this.  Just as a "fun" test, setup a test machine with
hotswap drives in a RAID 10 zfspool.  Add a hot spare for good
measure.  While the system is running, pull one of the hot swap drives
and watch ZFS eat up all of the memory trying to talk to the drive
that is not longer there until you get a kernel panic.  We had this on
Solaris (x86 and 64-bit installs).  I know pulling a drive isn't
necessarily exactly the same as a drive dying, but it still shouldn't
bring down the whole system.
(Paid) Sun support had no answer.

We also tested ZFS on a FreeBSD 7.0 beta, run bonnie++ with a test
file size larger then RAM, this too will eat up all available memory
and bring down the system.  Obviously this could be a bonnie issue,
but still due to the overwhelming complexity of ZFS, it makes me
nervous putting anything in production that would use it.  ZFS has a
lot of good features in theory, but like a lot of Sun software (NFS,
JAVA) tends to be a little over-engineered and bloated.

I don't intend to start a flame-war or anything thing like that, but
in my experience there are still too many potential problems to really
rely on it in production.  It could just be my inability to setup ZFS
properly.  I would just recommend extensive testing and attempts to
simulate drive failures before putting it into production.  If ZFS
ever gets to what it aspires to be, and then got combined with
FreeBSD, you would have IMHO the ultimate server OS, but right now,
FreeBSD with gmirror is pretty darn good.

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