<html>
<head>
<style><!--
.hmmessage P
{
margin:0px;
padding:0px
}
body.hmmessage
{
font-size: 10pt;
font-family:Verdana
}
--></style>
</head>
<body class='hmmessage'>
First, thanks for reply.<br><br>I'm interested in this issue because, in my research lab, we want to create a cloud using a lot of computer with max 2GB and 2 cores, and then deploy several (not just one or few like in a grid) VMs who requires more resources (such as 8 GB-8cores).<br><br>So we're interested in Opennebula capabilities.<br>Then I have more questions.<br>Reading your reply, I suppose this could be impossible because of the hypervisors used by Opennebula (Kvm, Xen). <br>There is an hypervisor that could be useful for our purpose? For example, vmware can span multiple machines?<br><br>Opennebula has ever been tested for deploying and managing virtual machines in a grid?<br><br>Thanks again for kindness.<br><br>Daniele Fetoni<br><br>> Date: Fri, 11 Jun 2010 15:39:19 +0200<br>> From: jelle@defekt.nl<br>> To: daniele.fetoni@hotmail.it<br>> CC: users@lists.opennebula.org<br>> Subject: Re: [one-users] Can I use more hosts for just one VM?<br>> <br>> On Fri, Jun 11, 2010 at 01:38:38PM +0200, Daniele Fetoni wrote:<br>> ><br>> > Maybe my question is stupid, but I found nothing in documentation, so<br>> > I want you to ask: is possible with opennebula create a VM using<br>> > resources from several hosts?<br>> ><br>> > I mean, if I have two cluster nodes with 2 cores each one, can I<br>> > deploy a VM requiring 3 cores?<br>> <br>> No you can't, the underlying hypervisors (KVM,Xen) cannot span multiple<br>> machines.<br>> <br>> This not suprising: cores need to talk to each other because they<br>> usually share state (memory, locks, etc). So, for this reason the<br>> communication channel between cores can become a bottleneck. Bandwidth<br>> between two chips in a modern machine is extremely high: around 100<br>> Gbit/s or more! (Contrast this with a 1Gbit/s network).<br>> <br>> Then there is latency and lots of other complicated issues, but you<br>> are entering grid-computing terrain here :-)<br>> <br>> <br>> Regards,<br>> Jelle.<br> <br /><hr />Un mondo di personalizzazioni per Messenger, PC e cellulare, <a href='http://www.pimpit.it/' target='_new'>scaricale gratis!</a></body>
</html>