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-users] streaming server on a virtual machine.

On Sat, Sep 26, 2009 at 4:42 PM, Mauro <mrsanna1@xxxxxxxxx> wrote:
> 2009/9/18 Jeff Sturm <jeff.sturm@xxxxxxxxxx>:
>> I don't see why not.  If you're concerned about latency you could always
>> pin the server to a physical CPU.
>> (Lately we've been doing a lot of physical-to-virtual migrations, and
>> I've found myself asking: "What kinds of servers do we have that should
>> never be virtual?"  There aren't many on that list.)
> You say that a streaming server can be installed on a virtual machine.
> I don't want to create any kind of disturb but I've asked the same
> question to the KVM mailing list and they said that a streaming server
> (I user red5), due to the high I/O traffic, it must absolutely not
> virtualized.

Here's my general point of view of that : one of the purposes of
virtualization is to consolidate servers with low utilization to
increase system utilization and reduce hardware requirements, thus
reducing cost.

Here's an over-simplified example: lets say your physical server is
capable of providing 2 GHz CPU and 100 Mbps network bandwidth, and
your streaming server will require 500 MHz CPU and 90 Mbps network.
Disk I/O is not an issue since all data is cached in memory (again,
this is just an example). With that setup and requirements, it's not a
good idea to virtualize the streaming server as it already have high
network utilization. The case is different if you have 1 Gbps NIC, or
if you have an extra 100 Mbps NIC that you can dedicate to domU
(either with dedicated bridge or PCI passthrough).

The limiting factor migh differ depending on usage. It could be CPU,
memory, disk (throughput and IOPS), or network. It could even be
latency (like with VOIP). In any case, it's best to determine what
your requirements are and what you're physical server is capable of
before deciding whether or not to go down virtualization route.


Xen-users mailing list