[libvirt-users] KVM incremental backup using CBT

Jd jd_jedi at convirture.com
Mon Oct 13 18:16:50 UTC 2014

On 10/13/14, 7:23 AM, Eric Blake wrote:
> On 10/12/2014 10:19 PM, Jd wrote:
> [please don't top-post on technical lists]
>> Thanks Kashyap,
>> The command line examples makes thing quite clear :)
>> rsync for image (large) files create a new file for every little
>> change,  that was the reason I started looking in to using dirty bitmaps.
> Upstream qemu still doesn't have persistent dirty bitmap tracking
> working yet; once patches land there, then we also need to get libvirt
> to interact with those new qemu features.  But yes, dirty bitmap
> tracking, so that you can track which portions of a file have changed
> rather than copying the entire file, is something that is technically
> feasible once the patches materialize.
Thank you.
I want to try this out in my environment for testing, what would you 
suggest ? I am ok with using qemu-monitor commands in the interim till 
things materializes in the libvirt level.

* Where can I start  ?
    qemu : http://wiki.qemu.org/ChangeLog/2.1  ?
    kvm   : do I need specific kvm or the following will work ? (see at 
the end)
    libvirt :update to 1.2.8 at least as you recommended to thomas.

* Where can I get relevant patches etc?  block-backup, anything else?

* With some modifications to following procedure,  can I get it a test 
environment for testing incremental backup ?


==== KVM Info ===
sudo modinfo kvm
filename: /lib/modules/3.13.0-24-generic/kernel/arch/x86/kvm/kvm.ko
license:        GPL
author:         Qumranet
srcversion:     57170F28A3DA376BDCD5012
intree:         Y
vermagic:       3.13.0-24-generic SMP mod_unload modversions
signer:         Magrathea: Glacier signing key
sig_key: 69:B0:D0:A7:9B:85:D9:06:21:70:6E:8D:06:60:4D:73:0B:35:9F:C0
sig_hashalgo:   sha512
parm:           ignore_msrs:bool
parm:           min_timer_period_us:uint
parm:           tsc_tolerance_ppm:uint
parm:           allow_unsafe_assigned_interrupts:Enable device 
assignment on platforms without interrupt remapping support. (bool)

More information about the libvirt-users mailing list