Re: [Qemu-devel] [PATCH v4 3/6] add backup related monitor commands

[Dietmar Maurer]

> The disk is the bottleneck, not memory bandwidth.  Hard disks only do
> 10-100 MB/sec and SSDs only do a couple 100 MB/sec.  Memory copy is
> insignificant compared to the I/O activity required to copy out the entire 
> disk
> image, not to mention delaying guest writes until we read the original data 
> from
> the disk.

Not to mention fusion-io card, which are currently at 6GB/s.