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 ? http://kashyapc.com/2014/03/10/notes-for-building-kvm-based-virtualization-c... Thanks /Jd ==== 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 depends: 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)