Re: strange vnd disk behavior in -current (with ffs2?)

[Markus W Kilbinger <mk%kilbi.de@localhost>]

>>>>> "Sarton" == Sarton O'Brien <bsd-xen%roguewrt.org@localhost> writes:

    Sarton> Adam Hamsik wrote:
    >> Hi, On Oct,Thursday 30 2008, at 11:09 PM, Markus W Kilbinger
    >> wrote:
    >>> 
    >>> dd if=/dev/zero of=temp.disk bs=1 seek=100000000 count=1
    >> 
    >> You are creating spare disk image here don't you ? AFAIK vnd
    >> doesnt support spare images for now.

    Sarton> Just to clarify, I think he meant sparse disk image. This
    Sarton> has been a problem/feature of vnd for some time. Try a
    Sarton> larger block size/count and no seek.

Ok, that would be the clean way, but:

- It takes a lot of time which I tried to avoid ;-)

- What happens to the 'seek=100000000' space/gap in my dd example?
  Shouldn't it be some kind of pre-allocated and really allocated when
  it's accessed?

- The reaction to my fdisk's usage is (at least) inadequate. An error
  message would be more helpful (instead of a kernel panic or just
  doing nothing). If it's a vnd(4) limitation it should be at least
  documented.

Markus.