[DRBD-user] DRBD, Xen, HVM and live migration

[Mark Deneen]

On Fri, Sep 23, 2011 at 12:34 PM, Felix Frank <ff at mpexnet.de> wrote:
> Hi,
>
> On 09/23/2011 06:29 PM, Mark Deneen wrote:
>> I didn't analyze it much, but with our hardware here I found little
>> performance difference between partition based and file based VM
>> storage.  Ours are exported over iscsi-scst if that makes a
>> difference.
>
> I believe it does.
>
> If your VMs use iSCSI bases storage, the network is likely your
> bottleneck (does iSCSI support Infiniband?).
>
> When your VM sits directly atop DRBD, hopefully your disks are the
> bottleneck. Image based virtual disks add a layer of indirection, as the
> host system needs to handle the file operations.
>
> Again, for some workloads, this may not be much of an issue.


Felix,

In this situation the network was faster than the disks, which were rather slow.

Mark