new jail utility is available. announcement.

[Adam Vande More]

On Wed, Jul 21, 2010 at 4:52 AM, Aiza <aiza21 at comclark.com> wrote:

>
>  Not yet, when I have a spare box I might, although I quite like using
>> zfs for jails as you can limit the disk usage dynamically per zfs
>> filesystem and I didnt see any support there yet, even basic support
>> like there is with ezjail would be nice.
>>
>>
> Zfs was left out because its over kill. Sparse image jails gives the same
> protection at a 10th of the overhead.


You didn't factor in slowness due to having a file-backed filesystem.  While
probably pretty low, it's definitely there and not good in an io heavy
jail.  Also, the host will have to mount a UFS based FS, and cache it so
you're going to have increased memory usage.

Ideal setup for an io intensive jaill(eg database) is to be bound to
compressed ZFS file-system, not a sparse image located on such a setup.

I'm not sure what overhead you're referring too.  If it's hard to tie into
your application, you are probably correct, but from a host perspective you
are increasing overhead.

There are advantages to sparse or raw file as well, it would be nice to have
a choice.

-- 
Adam Vande More