WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

[Xen-devel] Re: [RFC PATCH 35/35] Add Xen virtual block device driver.

Jeff Garzik wrote:
>Arjan van de Ven wrote:
>> On Fri, 2006-03-24 at 08:37 -0500, Jeff Garzik wrote:
>>> Jeff Garzik wrote:
>>>> In fact, SCSI should make a few things easier, because the notion of 
>>>> host+bus topology is already present, and notion of messaging is already 
>>>> present, so you don't have to recreate that in a Xen block device 
>>>> infrastructure.
>>> Another benefit of SCSI:  when an IBM hypervisor in the Linux kernel 
>>> switched to SCSI, that allowed them to replace several drivers (virt 
>>> disk, virt cdrom, virt floppy?) with a single virt-SCSI driver.
>
>> but there's a generic one for that: iSCSI
>> so in theory you only need to provide a network driver then ;)
>
>Talk about lots of overhead :)
>
>OTOH, I bet that T10 is acting at high speed, right this second, to form 
>a committee, and multiple sub-committees, to standardize SCSI 
>transported over XenBus.  SXP anyone?  :)

Actually SRP (which T10 has now stopped working on) fits the bill very
nicely.

I have to say that moving the IBM virtual drivers from a random
collection of unique drivers (viodisk, viotape, viocd) to a single
virtual SCSI HBA made life much easier.

There is a group (actually, at least two groups) working on SCSI
target infrastructures...once that is in place, I would expect we
could start hacking a Xen virtual HBA.

We looked at iSCSI as a transport (instead of SRP) but we felt that 
the added complexity made it unlikely that the average human could
successfully boot their virtual machine

Dave B

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>