Re: [Libvir] [PATCH] Block device and network stats (version 2)
On Tue, Aug 21, 2007 at 12:55:19PM +0100, John Levon wrote:
On Tue, Aug 21, 2007 at 03:37:41AM +0100, Daniel P. Berrange wrote:
> The Xen impl as coded only works for disks named xvdN, because the code for
> calculating device ID assumes xvdN device numbering scheme:
>
> device = 202 * 256 + minor;
What's with device numbering at all? Must we really repeat this crazy
Linuxism from xend in libvirt :(
We need to convert from 'xvda' into /local/domain/0/backend/vbd/[domid]/[device
num]
where 'device num' is a crazy ass number XenD calculaties using the formula
above. The other option is to just iterate over every backend node comparing
the device name field. O(n) vs O(1) xenstore queries.
Dan.
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