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-users

Re: [Xen-users] tap:ram anyone?

To: "Dylan Martin" <dmartin@xxxxxxxxxxxx>
Subject: Re: [Xen-users] tap:ram anyone?
From: "Todd Deshane" <deshantm@xxxxxxxxx>
Date: Fri, 9 Jan 2009 22:20:52 -0500
Cc: xen-users <xen-users@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Fri, 09 Jan 2009 19:21:48 -0800
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:reply-to :to:subject:cc:in-reply-to:mime-version:content-type :content-transfer-encoding:content-disposition:references; bh=F6nK057BgI7j0AwCDp9FADSTUcr/Mv9nNKIet/DSUVo=; b=QiqpI/Q9VIQmCVSX/IM/bi4H1GtBR8WCPFnW9zGIdkCKH1s9NbY1pKq+abufYu23EU BKpVjC/E3z/uv2sm+72s1gbbTJOhdTAbcAsav6wK6NVIoMCDcpahg0R0HMMRvIfccf9o 8YO9YzEFetp8ONKuEETvJoV/WfNowjCi6Hj5Q=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:reply-to:to:subject:cc:in-reply-to :mime-version:content-type:content-transfer-encoding :content-disposition:references; b=cVhtbqXsoclB0B4bhsLwd2dyI6dc63QyHRg+og8kJG3q5JMfTzPaFi9XOkcVp9HLqn 6QOHrni+RjaCLG+s+Z8S7X16tg+DsqmBrJ/RulD/wF7BXLe9gv5HuZq7VbO7srhKyu9b mxMUPdYeUqNXskljZyJngoRtA/xJOUirpoGA4=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <e1a4c7f60901091442v7ebd8992qc442dc2c3eb4631d@xxxxxxxxxxxxxx>
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <e1a4c7f60901091442v7ebd8992qc442dc2c3eb4631d@xxxxxxxxxxxxxx>
Reply-to: deshantm@xxxxxxxxx
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
On Fri, Jan 9, 2009 at 5:42 PM, Dylan Martin <dmartin@xxxxxxxxxxxx> wrote:
> Has anyone ever tried the 'ram' driver with blktap for block devices?
> It's mentioned here:
>
>  http://wiki.xensource.com/xenwiki/blktap
>
>    Fast shareable RAM disk between VMs (requires some form of
> cluster-based filesystem support e.g. OCFS2 in the guest kernel)
>
> and poking around the source, in tools/blktap there is a README
> (almost identical to the above web page) and the drivers themselves.
>
> I've been trying to get it to work on CentOS 5.2 to no avail.  Specifically:
>
>   block-attach domain 'tap:ram:/path/to/file' hdb w
>
> ..makes something appear in the output of block-list, but the domU
> doesn't react at all.  (nothing in dmesg, /dev/dhb is not found
> etc...)  Sadly, this is exactly the same thing that happens if you
> specify a bogus tap driver, (EG tap:wibble:/path/to/file).
>
> I've tried tap:aio and tap:sync and they both work.
>

I haven't tried it personally.

There has been very little development on it.

see:
http://lxr.mstier.de/Xen/source/xen_3.2.1/tools/blktap/drivers/block_ram.c?v=3.2.1
http://xen.markmail.org/search/?q=block_ram.c

Maybe some hints in the code and/or changes since the CentOS Xen version.

Cheers,
Todd

-- 
Todd Deshane
http://todddeshane.net
http://runningxen.com

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

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