| |
|
 |
|
 |
|
|
|
| |
|
|
xen-devel
Re: [Xen-devel] xen and virtual iron
Virtual Iron seems to me to be a mix of Xen and openMosix, combined
with a Distributed Shared Memory (which openMosix has as an option).
Scaling up applications in a DSM environment is hugely dependent on the
application. If all you have are HPC type applications, then Virtual
Iron might scale nicely, but then why would you pay for something which
stuff like openMosix provides for free? For most business apps, I
suspect that a DSM-based solution will not scale at all, or have a
detrimental impact on performance/thruput, due to the issues with true
and false sharing.
They do have a pretty console application, though.
Moshe
On Feb 16, 2005, at 7:57 AM, Andrew Theurer wrote:
Sean Harper wrote:
At Linuxworld a company called Virtual Iron is demoing a product that,
like Xen or VMWare, can break physical machines into virtual machines.
However, unlike Xen or VMWare, this product can also aggregate
physical
machines into virtual machines. In other words, it is possible for
the
user to specify that 3.5 cpus from 2 machines (2 from 1 and 1.5 from
another) be assigned to a virtual machine. When linux boots on that
virtual machine it simply looks like a 4 cpu machine (but 1 of the
cpus
is slower). Presumably there is a pretty big performance penalty for
sharing across machines, which they mitigate to some extent by
requiring
Infiniband.
It seems like most of the tricky work is around caching to optimize
the
performance across the slower communication bus (when sharing between
machines).
Hmm, sounds like a NUMA system, with a relatively low throughput and
high latency interconnect. Not sure if anyone would want to do this
on a workload where performance matters.
I suppose with a layer of abstraction like Xen, doing something like
this is feasible. You could leverage the NUMA code in the linux
kernel, but I would think you would need a very highly parallel
workload to make this effective, and if you have that, a cluster setup
would probably work just as well anyway.
-Andrew Theurer
-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real
users.
Discover which products truly live up to the hype. Start reading now.
http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/xen-devel
-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now.
http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/xen-devel
|
|
|
| |
|
Home