Re: Xen DomU zvol disk sizes

[Greg Troxel <gdt%lexort.com@localhost>]

Sebastian <sebastian%xenoserver.net@localhost> writes:

> I'm trying to setup a NetBSD 10.1 Dom0 and use ZFS zvols as virtual
> block devices. First I struggled creating a working configuration
> because the raw and block device files are in different
> subdirectories, but at the end I found the few notes in the NetBSD
> wiki.
>
> If I now create a zvol with 10G size and start a NetBSD 10.1 (PV mode)
> the zvol appears in the DomU, but the disk size inside the DomU is
> only 25% (2^2??). I tried with different zvol blockvolsizes but
> without any effect.
>
> Also DomUs in HVM mode report the wrong disk sizes.

Your report is very hard to follow because it contains your conclusions
not your raw data: what did you type and what was printed?

I created zvols:

  zfs create -p -V 16G tank0/vm/n9-i386
  newfs -O2 /dev/zvol/rdsk/tank0/vm/n9-i386
  zfs create -p -V 8G tank0/vm/n9-i386.swap

and then in my domU config

  disk = [
          'vdev=hda, target=/dev/zvol/dsk/tank0/vm/n9-i386',
          'vdev=hdb, target=/dev/zvol/dsk/tank0/vm/n9-i386.swap'
          ]

and in my domU

  xbd0 at xenbus0 id 768: Xen Virtual Block Device Interface
  xbd0: using event channel 12
  xbd1 at xenbus0 id 832: Xen Virtual Block Device Interface
  xbd1: using event channel 13
  xbd0: 16384 MB, 512 bytes/sect x 33554432 sectors
  xbd1: 8192 MB, 512 bytes/sect x 16777216 sectors

and it's all fine.

zfs get volblocksize (not sure what 'blockvolsizes' is)

  tank0/vm/n9-i386             volblocksize  8K        -
  tank0/vm/n9-i386.swap        volblocksize  8K        -