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/
Home Products Support Community News


Re: [Xen-API] Alternative to Vastsky?

To: Tim Titley <tim@xxxxxxxxxx>, xen-api@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-API] Alternative to Vastsky?
From: Henrik Andersson <henrik.j.andersson@xxxxxxxxx>
Date: Wed, 20 Apr 2011 14:33:46 +0300
Delivery-date: Wed, 20 Apr 2011 04:35:08 -0700
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; bh=zToogTgDOfmlGejaa7LD3gHxRKwOcXOKga0cAebzxes=; b=EQ5SmvJj+gro6FuzuyemHvlYSxPWQ0N1EAoMMf3PjW9ip18lKjKeEWIeBMiidFv8/h 0EwwVFsCfhgQ4iPV938TJC+bXe6oq77HkgUzdAWqzBqs4qB79FZ9k9mBoDRIZgWZ7d6r tllTVtaoNTDI0Ve3bjvdLGrlF2jrkIcrLjhLc=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=xn0am895TwnJduO8ZFrzWjgW3/ru9wLxRT1DfuM6NiGi+sntgcuA9M8mqpxK2FvQk6 g+rZO7RaxbJkeEleGCtTVZyVKORe6++WgEyOprUQmiLX8KEQc6OmQU6R/TPNu4geiv2H 3Rc5N91PIYeS31Fd8N3xbmtHvFFVeyYuVBYbY=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <4DAE986C.7060508@xxxxxxxxxx>
List-help: <mailto:xen-api-request@lists.xensource.com?subject=help>
List-id: Discussion of API issues surrounding Xen <xen-api.lists.xensource.com>
List-post: <mailto:xen-api@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-api>, <mailto:xen-api-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-api>, <mailto:xen-api-request@lists.xensource.com?subject=unsubscribe>
References: <4DAE085F.5040707@xxxxxxxxxx> <BANLkTinponoRXqtO85wCpfkpq+SHNMY_Rw@xxxxxxxxxxxxxx> <4DAE986C.7060508@xxxxxxxxxx>
Sender: xen-api-bounces@xxxxxxxxxxxxxxxxxxx
Since there is no official support for InfiniBand in XCP and some people have managed to get it working, others not so much, I wanted to tell how far I got with it and hopefully in time, get some sort of howto out of this. All those RDMA possibilities could come handy but I would be more than pleased if I could even use IPoIB. 

Hardware and setup I have for this project:

SuperMicro SuperServer (2026TT-H6IBQRF), each of the four nodes comes with integrated Mellanox ConnectX QDR Infiniband 40Gbps Controller w/ QSFP connector. I have cable between two nodes and while testing, I had two ubuntu server 10.04 installations and according to netperf I got unidirecitonal throughput of about 15000Mbit/s on IPoIB between two nodes.  

Where I got with IB support is pretty sad. Had OFED compile and install all the drivers and such on ddk after I added some repositorys and installed bunch of different things required. The thing is that after reboot, ddk vm just hangs on boot if I have pci passthrough enabled for the IB card to ddk. If I disable it, everything is fine, since there is no IB card present for the ddk to try and use the drivers with.

If there is some one with experience on ddk, and customising the dom0, I could do fresh xcp 1.0 install and give this willing person root priviledges to this machine, so he can try. If this person get's it working, we could make a how to out of it and I could even host a site that makes all the files and instructions needed freely availeable for everyone.

-Henrik Andersson

On 20 April 2011 11:25, Tim Titley <tim@xxxxxxxxxx> wrote:
Sounds interesting and definately worth looking into. You would not have the advantage of snapshots like you do with an LVM type solution, but it may pay off in some instances from a performance perspective.

I've never used InfiniBand, but I think you've just convinced me to go buy a few cheap adaptors and have a little play.

On 19/04/11 23:39, Henrik Andersson wrote:
Now that VastSky has been reported to be on hiatus atleast, I'dd like to propose GlusterFS as a candidate. It is well tested and actively developed and maintained project. I'm personally really interested in "RDMA version". It should provide really low latencies and since 40Gbit InfiniBand is a bargain compared to 10GbE, there should be more than enough throughput availeable.

This would require IB support on XCP but my thinking is, it would be beneficial in many other ways. For example I would imagine RDMA could be used with live migrates.

-Henrik Andersson

On 20 April 2011 01:10, Tim Titley <tim@xxxxxxxxxx> wrote:
Has anyone considered a replacement for the vastsky storage backend now that the project is officially dead (at least for now)?

I have been looking at Ceph ( http://ceph.newdream.net/ ). A suggestion to someone so inclined to do something about it, may be to use the Rados block device (RBD) and put an LVM storage group on it, which would require modification of the current LVM storage manager code - I assume similar to LVMOISCSI.

This would provide scalable, redundant storage at what I assume would be reasonable performance since the data can be striped across many storage nodes.

Development seems reasonably active and although the project is not officially production quality yet, it is part of the Linux kernel which looks promising, as does the news that they will be providing commercial support.

The only downside is that RBD requires a 2.6.37 kernel. For those "in the know" - how long will it be before this kernel makes it to XCP - considering that this vanilla kernel supposedly works in dom0 (I have yet to get it working)?

Any thoughts?



xen-api mailing list

xen-api mailing list

xen-api mailing list