Re: [Qemu-devel] [PATCH v4 4/6] introduce new vma archive format

[Dietmar Maurer]

> > We track zero regions at 4K level, and Cluster size is 64K.
> >
> > So I normally just use 1bit to store information about empty blocks.
> >
> > I thought that is quite good, but you obviously have a better idea?
> 
> Maybe I didn't understand right then. These zero regions are just for 
> describing
> empty sectors within non-empty clusters? 

I currently also write an entry for empty sectors. But this is only done as 
additional
error check, to prove that the backup tool wrote all data.