[CentOS-virt] performance differences between kvm/xen

Sat Oct 16 19:58:15 UTC 2010
Dennis Jacobfeuerborn <dennisml at conversis.de>

On 10/16/2010 08:11 PM, Pasi Kärkkäinen wrote:
> On Thu, Oct 14, 2010 at 02:16:42PM +0100, Bart Swedrowski wrote:
>> Hi Karanbir,
>>
>> On 14 October 2010 19:59, Karanbir Singh<mail-lists at karan.org>  wrote:
>>>
>>> On 10/14/2010 07:48 AM, Tom Bishop wrote:
>>>> I think xen is still on top in terms of performance and features....now
>>>
>>> that is indeed what it 'feels' like, but I'm quite keen on putting some
>>> numbers on that.
>>
>> I have done some testing some time ago on one of the EQ machines that
>> I got from hetzner.de.  Full spec of the machine was as following:
>>
>>    * Intel® Core??? i7-920
>>    * 8 GB DDR3 RAM
>>    * 2 x 750 GB SATA-II HDD
>>
>> It's nothing big but even though results are quite interesting.  All
>> tests were performed on CentOS 5.5 x86_64 with PostgreSQL 8.4 (from
>> CentOS repos).
>>
>
> Note that 64bit Xen guests should be HVM, not PV, for best performance.
> Xen HVM guests obviously still need to have PV-on-HVM drivers installed.
>
> 32bit Xen guests can be PV.

Hm, why would HVM be faster than PV for 64 bit guests?

Regards,
   Dennis