Re: [Qemu-devel] Adding Disk-Level Introspection to QEMU

[Stefan Hajnoczi <stefanha@gmail.com>]

On Tue, Apr 23, 2013 at 03:11:26PM -0400, Wolfgang Richter wrote:
> On Tue, Apr 23, 2013 at 2:31 PM, Wolfgang Richter <wolf@cs.cmu.edu> wrote:
> 
> > On Tue, Apr 23, 2013 at 2:21 PM, Stefan Hajnoczi <stefanha@gmail.com>wrote:
> >
> >> Eric's suggestion to use NBD makes sense to me.  The block-backup code
> >> can be extended fairly easier using sync mode=none (do not perform a
> >> background copy of the entire disk) and by disabling the bitmap
> >> (essentially "tap" mode).
> >
> >
> Also, as another thought, I think I can actually use the bitmap to implement
> an optimization.  In my code, I already use a bitmap to determine which
> sectors I want to introspect (ignoring portions of the disk greatly reduces
> required bandwidth and overhead; swap space for example isn't generally
> interesting unless you can interpret memory as well).   So I think I can
> adapt
> my code here as well.

Cool.  By the way, do you actually care about the data being written or
just which sectors were touched?

Stefan