Xen project Mailing List

Somehow i dont get the concept of running a claimed multi-million dollar enterprise that he claims is loosing so much due to downtime in a virtual environment either
let alone using windows for this type of task, but hey to each their own. the only right plan is a good plan, the only good plan is a redundent plan
Id be afraid to ask what happens if they were to experience a catastrophic event, speaking from experience of Hurricanes, Earthquakes, Typhoons and Tsunamis
What the escape plans ?? and you blame XEN for not functioning in a virtual environment, Id have your job and your bosses if you worked for me!
I wonder who sleeps better at night, you, your boss or me!

Tao Shen schrieb:

First of all, your boss should fire you for saying "windows 2008 sql server runs perfectly unless windows crashes"

Secondly, whoever delivered the xen solution on your 200k per day production server should be fired for not understanding the concept of single point of failure.

Now that you learned the lesson at 5k per hour,you should dump virtual machines and have redundant physical machines for mission critical services on your network. For 200k a day, that is 72million a year revenue, you should have a budget of at least 5 to 7 mil to handle redundancy issues, which means double or even triple redundancy networks and San storage for database servers.

Lastly, I think that either your boss bluffed you with 5k per hour cost of downtime, or you did, since I cannot imagine such incompetent people running a business valued at 15 times earning or hundreds of millions if your 72 million revenue figure is indeed correct.

Btw, xen is maintained by citrix, not Novell.

On Jul 20, 2008, at 11:36 AM, "Venefax" <venefax@xxxxxxxxx> wrote:

SQL Server only runs in Windows. I am now actually learning DB2 in order to
use a Linux-based database. But of course I am not dumb to put my entire
business on a database I cannot support, yet, the way I do with SQL Server.
And the beauty is the with XEN-Windows 2008, SQL Server runs perfectly,
unless Windows crashes.

-----Original Message-----
From: Florian Manschwetus [mailto:florianmanschwetus@xxxxxx]
Sent: Sunday, July 20, 2008 12:30 PM
To: Mark Williamson
Cc: xen-users@xxxxxxxxxxxxxxxxxxx; Venefax; jim burns
Subject: Re: [Xen-users] The death of XEN by Novell

Mark Williamson schrieb:

On Sunday 20 July 2008, jim burns wrote:

On Sun July 20 2008 9:51:52 am Venefax wrote:

The Novell engineer showed me a technical document, which I did not

write

the number, on the Novell web site, where it said: windows SMP using the
Novell driver crashes.

That's what I thought - the problem is with Novell's PV drivers, not Xen.
James had some initial problems with SMP also.

Right, that's important. Novell's PV drivers are their code so those

drivers

might have limitations that plain Xen does not. Presumably it would be
possible to run using fully emulated IO instead of PV drivers but I

imagine

this could have performance problems in your configuration. Could be

worth a

try, if you can afford to experiment.

If the Windows VMs themselves are crashing due to Novell's PV drivers then

I'm

afraid this limitation / problem is really Novell's responsibility and

they

would be the best people to approach for assistance / complaints. The

code

for those drivers isn't open, so only Novell can fix them. If the Novell

PV

drivers are somehow crashing your Linux domains or dom0 or Xen itself then

that might be a Xen bug and it would be useful to post more details here.

For comparison, Citrix/XenSource supply with their product PV drivers for
Windows that are - AFAIK - a different codebase and may not have these
limitations. So do Virtual Iron, for their Xen-based product. Both of

these

can only be used with their respective commercial hypervisors, AFAIK.

James

Harper's PV drivers for Windows are GPL but still under development and so

I

doubt they'd be recommended for heavy production use.

There are a lot of different PV driver solutions for Windows about and

none of

them are officially part of the OSS Xen project; only one of them is even
Open Source.

I really wonder why you run your SQL servers in windows and all the rest
in Linux???
I asume especially for databases is Windows a bad base, but i have a
win20008 sharepoint running on xen 3.2.1 with 2 vcpus it works great and
stable with james drives.
And if you like to use this single Box, you may ask SUN (Solaris and
SunXvm).

florian

I use a SIP Server on the Linux side, talking hundreds of times per
second to SQL Server, so I need SMP 8 ways on both ends.

Something I've never seen you actually say is that you *tried* vcpu=1,

and

the performance was bad. So far, it sounds like theory to me. Even with 1
vcpu, playing with scheduling weights should help.

Venefax, are you able to try this?

Thank you,
Mark

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users

__________ Hinweis von ESET NOD32 Antivirus, Signaturdatenbank-Version 3283 (20080721) __________

E-Mail wurde geprüft mit ESET NOD32 Antivirus.

http://www.eset.com

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users