[development] Drupal 5.1 on RHEL5 - virtualized

[Anton]

On 22/03/07, Boerland, Bert <bert.boerland at getronics.com> wrote:
> Please note that this hardware doenst do hardware based VT and
> hence your results will be off compared with "new" servers
> (AMD/Pacifica, Intel/VT)

That's only if you actually use the full virtualisation methods. Even
on the new servers, most people running Linux guests will probably
just want to stick with the older para-virtualisation method as it is
generally faster (there are a few exceptions), more mature and seems
(to me at least) to be a little easier to admin.

Of course the new servers open up lots of other possibilities like
running Windows or other unmodified OSes as guests. Also the new full
virtualisation hardware lets you mix up 32bit vs 64bit, PAE vs non PAE
kernels as guests. With current versions of Xen, the Dom0 and DomUs
need to be the same in terms of 32bit vs 64bit and PAE etc.

Anyway, swinging this back towards Drupal, it was good to see that in
the second test Xen doesn't add very much overhead at all. This could
mean though that this test was limited by a RAM or CPU bottleneck - I
have heard that Xen performance can take a hit when I/O becomes the
bottleneck.

And Berts Intel benchmark link above suggests that a file I/O
bottleneck chould be one of the scenarios where you want full
virtualisation instead of paravirtualisation :)

-- 
Cheers
Anton