[Users] about live snapshot and qemu-kvm

[Douglas Schilling Landgraf]

On 01/01/2014 06:24 AM, Gianluca Cecchi wrote:
> On Wed, Jan 1, 2014 at 4:38 AM, R P Herrold  wrote:
>
>>
>> Out of curiousity, _what_ build environment 'flags' do you
>> all, participating in this thread, refer to? -- the thread
>> does not enumerate them explicitly, and one cannot expect to
>> hit by 'indirect fire', a target not exposed
>>
>> With best regards, this New Year's eve
>
> I'm far from being a programmer, but as I went to compare build
> environments, between
> qemu-kvm-rhev-0.12.1.2-2.415.el6_5.3.src.rpm
> and
> qemu-kvm-0.12.1.2-2.415.el6_5.3.src.rpm
> in related spec file I see
> [g.cecchi at tekkaman SPECS]$ diff qemu-kvm.spec.upstream qemu-kvm.spec.rhev
> 3c3
> < %define rhev 0
> ---
>> %define rhev 1
> 12928a12929
>>>>>>>>> rhel-6.5
>
> and apart other probably not trivial implications, such as guest agent
> part, I see that the "configure" command takes one extra argument in
> base RH EL 6.5, that is
>
> --disable-rhev-features
>
> The only patch file containing this keyword is
>
> kvm-Block-streaming-disable-for-RHEL.patch
>
> and inside it there are these lines that impacts configure options and
> related built qemu-kvm:
>
> --- a/configure
> +++ b/configure
> @@ -286,6 +286,7 @@ spice=""
>   smartcard=""
>   smartcard_nss=""
>   live_snapshots="yes"
> +block_stream="yes"
>   usb_redir=""
>
>   # OS specific
> @@ -686,10 +687,22 @@ for opt do
>     ;;
>     --enable-live-snapshots) live_snapshots="yes"
>     ;;
> +  --disable-block-stream) block_stream="no"
> +  ;;
> +  --enable-block-stream) block_stream="yes"
> +  ;;
>     --disable-usb-redir) usb_redir="no"
>     ;;
>     --enable-usb-redir) usb_redir="yes"
>     ;;
> +  --disable-rhev-features)
> +       live_snapshots="no";
> +       block_stream="no";
> +  ;;
> +  --enable-rhev-features)
> +       live_snapshots="yes";
> +       block_stream="yes";
> +  ;;
>     *) echo "ERROR: unknown option $opt"; show_help="yes"
>     ;;
>     esac
> @@ -863,8 +876,12 @@ echo "  --disable-smartcard-nss  disable
> smartcard nss support"
>   echo "  --enable-smartcard-nss   enable smartcard nss support"
>   echo "  --disable-live-snapshots disable live block device snapshot support"
>   echo "  --enable-live-snapshots  enable live block device snapshot support"
> +echo "  --disable-block-stream   disable block streaming support"
> +echo "  --enable-block-stream    enable block streaming support"
>   echo "  --disable-usb-redir      disable usb network redirection support"
>   echo "  --enable-usb-redir       enable usb network redirection support"
> +echo "  --disable-rhev-features  disable RHEV-only features"
> +echo "  --enable-rhev-features   enable RHEV-only features"
>   echo ""
>   echo "NOTE: The object files are built at the place where configure
> is launched"
>   exit 1
> @@ -2271,6 +2288,7 @@ echo "Trace backend     $trace_backend"
>   echo "spice support     $spice"
>   echo "nss used          $smartcard_nss"
>   echo "Live snapshots    $live_snapshots"
> +echo "Block streaming   $block_stream"
>   echo "xfsctl support    $xfs"
>   echo "usb net redir     $usb_redir"
>
> @@ -2526,6 +2544,10 @@ if test "$live_snapshots" = "yes" ; then
>     echo "CONFIG_LIVE_SNAPSHOTS=y" >> $config_host_mak
>   fi
>
> +if test "$block_stream" = "yes" ; then
> +  echo "CONFIG_BLOCK_STREAM=y" >> $config_host_mak
> +fi
> +
>   if test "$usb_redir" = "yes" ; then
>     echo "CONFIG_USB_REDIR=y" >> $config_host_mak
>   fi
>
> I don't think the rhev argument has instead implications in upstream
> source qemu-kvm-0.12.1.2.tar.gz
> So I think that if you want to dig more and if you have more
> competences, you have to see the full spec file and the full patch
> above.
>
> Files downloaded here:
>
> upstream
> http://ftp.redhat.com/redhat/linux/enterprise/6Server/en/os/SRPMS/qemu-kvm-0.12.1.2-2.415.el6_5.3.src.rpm
>
> rhev
> http://ftp.redhat.com/redhat/linux/enterprise/6Server/en/RHEV/SRPMS/qemu-kvm-rhev-0.12.1.2-2.415.el6_5.3.src.rpm
>

Just for the record, we have setup a jenkins job to rebuild qemu-kvm for 
el6 until we get it officially from centos:
http://jenkins.ovirt.org/view/Packaging/job/qemu-kvm-rhev_create_rpms_el6/

-- 
Cheers
Douglas