Re: [Qemu-devel] Moving beyond image files

2011-03-21 Thread Stefan Hajnoczi
On Mon, Mar 21, 2011 at 3:05 PM, Anthony Liguori wrote: > 2) The daemon maintains metadata for each image that includes an extent > mapping and then a clustered allocated bitmap within each extent (similar to > FVD). s/clustered allocated bitmap/cluster allocation bitmap/ ? > 3) All writes resul

Re: [Qemu-devel] Moving beyond image files

2011-03-21 Thread Anthony Liguori
On 03/21/2011 10:16 AM, Alexander Graf wrote: On 21.03.2011, at 16:05, Anthony Liguori wrote: 5) Copy-on-write references potentially become very interesting for image streaming because you can avoid any I/O for blocks that are already stored locally. This is not fully baked yet but I thoug

Re: [Qemu-devel] Moving beyond image files

2011-03-21 Thread Alexander Graf
On 21.03.2011, at 16:05, Anthony Liguori wrote: > We've been evaluating block migration in a real environment to try to > understand what the overhead of it is compared to normal migration. The > results so far are pretty disappointing. The speed of local disks ends up > becoming a big bottl

[Qemu-devel] Moving beyond image files

2011-03-21 Thread Anthony Liguori
We've been evaluating block migration in a real environment to try to understand what the overhead of it is compared to normal migration. The results so far are pretty disappointing. The speed of local disks ends up becoming a big bottleneck even before the network does. This has got me thin