Xen users - Nov 2005 - Use hard drive as physical mem for xen vm

Hi all,

I''ve got a machine that should serve 2 XenUs as mysql cluster nodes
with
realy big memory consumption. As mysql cluster will need approx. 4GB memory
on each XenU, I wondered if I could use hard disc space as memory for the
XenU that appears as real physical memory within the VM. Swap is no
alternative as mysql cluster nodes check the physical memory and if that is
not enough, they will not work.

How can I do that?

Thanks for your help!

Sincerly,
Oliver Neumann


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

The short answer is NO. 

In longer text: Xen has no idea about swapping, which is really what you
want it to do [because you want Xen to say that there is 8GB of RAM
where there really isn''t]. In Xen, all management of swapping is done
in
the guest-OS, so Xen doesn''t have any capability of managing swapping
[in fact, Xen itself doesn''t even have a hard disk driver in it]. 

The only solution to your problem would be to have the required amount
of physical memory for the server, i.e. 8GB (+ a little bit) if you run
2x 4GB servers on one machine.

--
Mats 

-----Original Message-----
From: xen-users-bounces@lists.xensource.com
[mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Oliver
Neumann [New Identity AG]
Sent: 11 November 2005 13:52
To: xen-users@lists.xensource.com
Subject: [Xen-users] Use hard drive as physical mem for xen vm

Hi all,

I''ve got a machine that should serve 2 XenUs as mysql cluster nodes
with
realy big memory consumption. As mysql cluster will need approx. 4GB
memory
on each XenU, I wondered if I could use hard disc space as memory for
the
XenU that appears as real physical memory within the VM. Swap is no
alternative as mysql cluster nodes check the physical memory and if that
is
not enough, they will not work.

How can I do that?

Thanks for your help!

Sincerly,
Oliver Neumann


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



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

On Friday 11 November 2005 14:51, Oliver Neumann [New Identity AG]
wrote:
> Hi all,
>
> I''ve got a machine that should serve 2 XenUs as mysql cluster
nodes with
> realy big memory consumption. As mysql cluster will need approx. 4GB memory
> on each XenU, I wondered if I could use hard disc space as memory for the
> XenU that appears as real physical memory within the VM. Swap is no
> alternative as mysql cluster nodes check the physical memory and if that is
> not enough, they will not work.
>
> How can I do that?
Invest a few extra € and put 8Gigs of ram in that server?
Reconfigure the mysql instances to run with just 2GB?

Seriously, mysql wants physical ram there for a reason, if that memory is 
swapped, it would be faster for mysql to just read the blocks from its db 
files.

/Ernst

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

Hmpf, to bad. Thanks for your answer.


-----Ursprüngliche Nachricht-----
Von: Petersson, Mats [mailto:mats.petersson@amd.com] 
Gesendet: Freitag, 11. November 2005 14:58
An: Oliver Neumann [New Identity AG]; xen-users@lists.xensource.com
Betreff: RE: [Xen-users] Use hard drive as physical mem for xen vm

The short answer is NO. 

In longer text: Xen has no idea about swapping, which is really what you
want it to do [because you want Xen to say that there is 8GB of RAM
where there really isn''t]. In Xen, all management of swapping is done
in
the guest-OS, so Xen doesn''t have any capability of managing swapping
[in fact, Xen itself doesn''t even have a hard disk driver in it]. 

The only solution to your problem would be to have the required amount
of physical memory for the server, i.e. 8GB (+ a little bit) if you run
2x 4GB servers on one machine.

--
Mats 

-----Original Message-----
From: xen-users-bounces@lists.xensource.com
[mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Oliver
Neumann [New Identity AG]
Sent: 11 November 2005 13:52
To: xen-users@lists.xensource.com
Subject: [Xen-users] Use hard drive as physical mem for xen vm

Hi all,

I''ve got a machine that should serve 2 XenUs as mysql cluster nodes
with
realy big memory consumption. As mysql cluster will need approx. 4GB
memory
on each XenU, I wondered if I could use hard disc space as memory for
the
XenU that appears as real physical memory within the VM. Swap is no
alternative as mysql cluster nodes check the physical memory and if that
is
not enough, they will not work.

How can I do that?

Thanks for your help!

Sincerly,
Oliver Neumann


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



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

>> I''ve got a machine that should serve 2 XenUs as mysql cluster
nodes with
>> realy big memory consumption. As mysql cluster will need approx. 4GB
memory
>> on each XenU, I wondered if I could use hard disc space as memory for
the
>> XenU that appears as real physical memory within the VM. Swap is no
>> alternative as mysql cluster nodes check the physical memory and if
that is
>> not enough, they will not work.
>>
>> How can I do that?
>Invest a few extra € and put 8Gigs of ram in that server?
>Reconfigure the mysql instances to run with just 2GB?
>Seriously, mysql wants physical ram there for a reason, if that memory is 
>swapped, it would be faster for mysql to just read the blocks from its db 
>files.
No, with that amount of data in our databases we already calculated, that we 
need at least 4GB only for each cluster node, so we woul dhave to buy at least
8GB of ECC RAM which isn''t really cheap. The
''problem'' is that we only need to
test an application on a cluster, after that we don''t need that big
amount of
memory in that machine so the money is somehow wasted. As for the performance:
That
is irrelevant, the cluster does not need to be fast (it actually can be damn
slow!).

Unfortunately there seems to be no chance to save the money using Xen with
harddisc
emulated physical RAM, right?


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

If MySQL really needs that much memory, doing swapping externally to the guest 
would likely lead to awful performance (even if we could do it...), so
you''d
be shooting yourself in the foor.

Xen 3.0 will let you use all the 8Gig under PAE or x86_64 mode.

Cheers,
Mark

On Friday 11 November 2005 14:12, Oliver Neumann [New Identity AG]
wrote:
> Hmpf, to bad. Thanks for your answer.
>
>
> -----Ursprüngliche Nachricht-----
> Von: Petersson, Mats [mailto:mats.petersson@amd.com]
> Gesendet: Freitag, 11. November 2005 14:58
> An: Oliver Neumann [New Identity AG]; xen-users@lists.xensource.com
> Betreff: RE: [Xen-users] Use hard drive as physical mem for xen vm
>
> The short answer is NO.
>
> In longer text: Xen has no idea about swapping, which is really what you
> want it to do [because you want Xen to say that there is 8GB of RAM
> where there really isn''t]. In Xen, all management of swapping is
done in
> the guest-OS, so Xen doesn''t have any capability of managing
swapping
> [in fact, Xen itself doesn''t even have a hard disk driver in it].
>
> The only solution to your problem would be to have the required amount
> of physical memory for the server, i.e. 8GB (+ a little bit) if you run
> 2x 4GB servers on one machine.
>
> --
> Mats
>
> -----Original Message-----
> From: xen-users-bounces@lists.xensource.com
> [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Oliver
> Neumann [New Identity AG]
> Sent: 11 November 2005 13:52
> To: xen-users@lists.xensource.com
> Subject: [Xen-users] Use hard drive as physical mem for xen vm
>
> Hi all,
>
> I''ve got a machine that should serve 2 XenUs as mysql cluster
nodes with
> realy big memory consumption. As mysql cluster will need approx. 4GB
> memory
> on each XenU, I wondered if I could use hard disc space as memory for
> the
> XenU that appears as real physical memory within the VM. Swap is no
> alternative as mysql cluster nodes check the physical memory and if that
> is
> not enough, they will not work.
>
> How can I do that?
>
> Thanks for your help!
>
> Sincerly,
> Oliver Neumann
>
>
> _______________________________________________
> Xen-users mailing list
> Xen-users@lists.xensource.com
> http://lists.xensource.com/xen-users
>
>
>
> _______________________________________________
> Xen-users mailing list
> Xen-users@lists.xensource.com
> http://lists.xensource.com/xen-users
_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

Well, I actually think that you''re trying to do something that you
really shouldn''t. Like Ernst said, if you haven''t actually got
the memory available to do something, then it''s better to let the db
manager read the db-data from the disk, than to make it believe that
it''s got the memory there and cache something, which ends up being
swapped in and out. You either HAVE the memory, or you tell the DB manager that
it''s not got that much memory, and let it handle this fact in whatever
way it can. You get WORSE performance from swapping than you''d get from
letting the DB know that you have less memory... Unless of course what
you''re trying to do is something really weird... ;-)

--
Mats

-----Original Message-----
From: Oliver Neumann [New Identity AG] [mailto:oliver.neumann@newidentity.de] 
Sent: 11 November 2005 14:13
To: Petersson, Mats; xen-users@lists.xensource.com
Subject: AW: [Xen-users] Use hard drive as physical mem for xen vm

Hmpf, to bad. Thanks for your answer.


-----Ursprüngliche Nachricht-----
Von: Petersson, Mats [mailto:mats.petersson@amd.com] 
Gesendet: Freitag, 11. November 2005 14:58
An: Oliver Neumann [New Identity AG]; xen-users@lists.xensource.com
Betreff: RE: [Xen-users] Use hard drive as physical mem for xen vm

The short answer is NO. 

In longer text: Xen has no idea about swapping, which is really what you
want it to do [because you want Xen to say that there is 8GB of RAM
where there really isn''t]. In Xen, all management of swapping is done
in
the guest-OS, so Xen doesn''t have any capability of managing swapping
[in fact, Xen itself doesn''t even have a hard disk driver in it]. 

The only solution to your problem would be to have the required amount
of physical memory for the server, i.e. 8GB (+ a little bit) if you run
2x 4GB servers on one machine.

--
Mats 

-----Original Message-----
From: xen-users-bounces@lists.xensource.com
[mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Oliver
Neumann [New Identity AG]
Sent: 11 November 2005 13:52
To: xen-users@lists.xensource.com
Subject: [Xen-users] Use hard drive as physical mem for xen vm

Hi all,

I''ve got a machine that should serve 2 XenUs as mysql cluster nodes
with
realy big memory consumption. As mysql cluster will need approx. 4GB
memory
on each XenU, I wondered if I could use hard disc space as memory for
the
XenU that appears as real physical memory within the VM. Swap is no
alternative as mysql cluster nodes check the physical memory and if that
is
not enough, they will not work.

How can I do that?

Thanks for your help!

Sincerly,
Oliver Neumann


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





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

> No, with that amount of data in our databases we already calculated, that
> we need at least 4GB only for each cluster node, so we woul dhave to buy at
> least 8GB of ECC RAM which isn''t really cheap. The
''problem'' is that we
> only need to test an application on a cluster, after that we don''t
need
> that big amount of memory in that machine so the money is somehow wasted.
> As for the performance: That is irrelevant, the cluster does not need to be
> fast (it actually can be damn slow!).
>
> Unfortunately there seems to be no chance to save the money using Xen with
> harddisc emulated physical RAM, right?
Can you really not configure MySQL to have a smaller RAM footprint?

If you really want to be evil, you could configure a 4Gig domain, start MySQL 
and then *balloon* it down to 2Gig.  MySQL would still see a 4Gig machine, 
just with lots of memory allocated by the kernel...  In reality that 
"allocated" memory is given back to Xen.

You could then do the same for the other MySQL domU (if they don''t
initially
fit in memory at once, suspend the first one to disk).

You should be able to get them both fitting in memory, although you''ll 
probably be well advised to configure them both with swap internally ;-)

Have fun; if you do try this please let us know how it goes.  It''s such
an
utterly twisted thing to do, I''m very curious to find out if it works!

Cheers,
Mark

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

> Unfortunately there seems to be no chance to save the money using Xen with
harddisc
> emulated physical RAM, right?
You could (in theory) hack the (domU) kernel to report to userland tools 
more ram than it realy has when the extra is actualy being swaped (by 
the domU kernel, not xen)... :)

-- 
Best regards, Black Dew.
=============================~ bdew@bdew.yi.org ~ ICQ:2666606 ~ 2:400/567 ~

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

On Friday 11 November 2005 15:15, Oliver Neumann [New Identity AG]
wrote:
> >> I''ve got a machine that should serve 2 XenUs as mysql
cluster nodes with
> >> realy big memory consumption. As mysql cluster will need approx.
4GB
> >> memory on each XenU, I wondered if I could use hard disc space as
memory
> >> for the XenU that appears as real physical memory within the VM.
Swap is
> >> no alternative as mysql cluster nodes check the physical memory
and if
> >> that is not enough, they will not work.
> >>
> >> How can I do that?
> >
> >Invest a few extra € and put 8Gigs of ram in that server?
> >Reconfigure the mysql instances to run with just 2GB?
> >Seriously, mysql wants physical ram there for a reason, if that memory
is
> >swapped, it would be faster for mysql to just read the blocks from its
db
> >files.
>
> No, with that amount of data in our databases we already calculated, that
> we need at least 4GB only for each cluster node, so we woul dhave to buy at
> least 8GB of ECC RAM which isn''t really cheap. The
''problem'' is that we
> only need to test an application on a cluster, after that we don''t
need
> that big amount of memory in that machine so the money is somehow wasted.
> As for the performance: That is irrelevant, the cluster does not need to be
> fast (it actually can be damn slow!).
>
> Unfortunately there seems to be no chance to save the money using Xen with
> harddisc emulated physical RAM, right?
As Mats pointed out, xen doesn''t know about harddrives, so it
can''t do any
swapping itself. 
Maybe you''ll have more luck with a virtualization method running at a
higher
level like linux-vserver or vmware or perhaps an emulation like qemu.

/Ernst

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

I understand your point - but we need to test the application on a mysql
cluster and mysql cluster ONLY works with memory. So I have to waste all the
money to just test the application and afterwards I''ve got 8GB on
memory I
don''t need. That''s what I call weird :-)

*AND* performance does not matter at all, a simple mysql query can use up to
1 hour or so, that''s not bothering me. I''m just triying to
save money ;-)

But I got your point, that this will obviously not work in Xen.


-----Ursprüngliche Nachricht-----
Von: Petersson, Mats [mailto:mats.petersson@amd.com] 
Gesendet: Freitag, 11. November 2005 15:19
An: Oliver Neumann [New Identity AG]; xen-users@lists.xensource.com
Betreff: RE: [Xen-users] Use hard drive as physical mem for xen vm

Well, I actually think that you''re trying to do something that you
really
shouldn''t. Like Ernst said, if you haven''t actually got the
memory available
to do something, then it''s better to let the db manager read the
db-data
from the disk, than to make it believe that it''s got the memory there
and
cache something, which ends up being swapped in and out. You either HAVE the
memory, or you tell the DB manager that it''s not got that much memory,
and
let it handle this fact in whatever way it can. You get WORSE performance
from swapping than you''d get from letting the DB know that you have
less
memory... Unless of course what you''re trying to do is something really
weird... ;-)

--
Mats

-----Original Message-----
From: Oliver Neumann [New Identity AG]
[mailto:oliver.neumann@newidentity.de] 
Sent: 11 November 2005 14:13
To: Petersson, Mats; xen-users@lists.xensource.com
Subject: AW: [Xen-users] Use hard drive as physical mem for xen vm

Hmpf, to bad. Thanks for your answer.


-----Ursprüngliche Nachricht-----
Von: Petersson, Mats [mailto:mats.petersson@amd.com] 
Gesendet: Freitag, 11. November 2005 14:58
An: Oliver Neumann [New Identity AG]; xen-users@lists.xensource.com
Betreff: RE: [Xen-users] Use hard drive as physical mem for xen vm

The short answer is NO. 

In longer text: Xen has no idea about swapping, which is really what you
want it to do [because you want Xen to say that there is 8GB of RAM
where there really isn''t]. In Xen, all management of swapping is done
in
the guest-OS, so Xen doesn''t have any capability of managing swapping
[in fact, Xen itself doesn''t even have a hard disk driver in it]. 

The only solution to your problem would be to have the required amount
of physical memory for the server, i.e. 8GB (+ a little bit) if you run
2x 4GB servers on one machine.

--
Mats 

-----Original Message-----
From: xen-users-bounces@lists.xensource.com
[mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Oliver
Neumann [New Identity AG]
Sent: 11 November 2005 13:52
To: xen-users@lists.xensource.com
Subject: [Xen-users] Use hard drive as physical mem for xen vm

Hi all,

I''ve got a machine that should serve 2 XenUs as mysql cluster nodes
with
realy big memory consumption. As mysql cluster will need approx. 4GB
memory
on each XenU, I wondered if I could use hard disc space as memory for
the
XenU that appears as real physical memory within the VM. Swap is no
alternative as mysql cluster nodes check the physical memory and if that
is
not enough, they will not work.

How can I do that?

Thanks for your help!

Sincerly,
Oliver Neumann


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





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

>Can you really not configure MySQL to have a smaller RAM footprint?
Unfortunately no - mysql itself recommends even with a small amount of data
at least 
16GB RAM, but we calculated that it will run with 4GB in our case, but that
is the
limit we have to support to the domain!
>If you really want to be evil, you could configure a 4Gig domain, start
MySQL 
>and then *balloon* it down to 2Gig.  MySQL would still see a 4Gig machine, 
>just with lots of memory allocated by the kernel...  In reality that 
>"allocated" memory is given back to Xen.
Urgh, that is realy ''evil'' and I don''t think that
this will lead to a stable
mysql
cluster node instead I remeber that mysql cluster nodes takes all memory he
can get
as buffer, so if you size this down that heavily, the cluster node will
probably
die!
>Have fun; if you do try this please let us know how it goes.  It''s
such an
>utterly twisted thing to do, I''m very curious to find out if it
works!
:-) Sorry, but I think this is no alternative for me.


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

On Fri, Nov 11, 2005 at 03:15:48PM +0100, Oliver Neumann [New Identity AG]
wrote:
> >> I''ve got a machine that should serve 2 XenUs as mysql
cluster nodes with
> >> realy big memory consumption. As mysql cluster will need approx.
4GB memory
> >> on each XenU, I wondered if I could use hard disc space as memory
for the
> >> XenU that appears as real physical memory within the VM. Swap is
no
> >> alternative as mysql cluster nodes check the physical memory and
if that is
> >> not enough, they will not work.
> >>
> >> How can I do that?
> 
> >Invest a few extra ??? and put 8Gigs of ram in that server?
> >Reconfigure the mysql instances to run with just 2GB?
> >Seriously, mysql wants physical ram there for a reason, if that memory
is
> >swapped, it would be faster for mysql to just read the blocks from its
db
> >files.
> 
> No, with that amount of data in our databases we already calculated, that
we
> need at least 4GB only for each cluster node, so we woul dhave to buy at
least
> 8GB of ECC RAM which isn''t really cheap. The
''problem'' is that we only need to
> test an application on a cluster, after that we don''t need that
big amount of
> memory in that machine so the money is somehow wasted. As for the
performance: That
> is irrelevant, the cluster does not need to be fast (it actually can be
damn slow!).
I''m still really confused here.  How damn slow can it be?  If you have
an
application that thinks it is in full memory (and needs full memory), and it
isn''t, then you''ll probably see in the neighborhood of a 1000
x slow down
(or worse).  So an operation that normally takes 1 second, would instead 20
minutes.

If we take that 1000x figure, and assume that a burn in test for the cluster
would take 1 hr (pretty small amount) under real ram, then the math states
that it would take 42 days to complete under emulated ram!

That seems a really bad way to test the functionality of the cluster, unless
you have 4 years you can wait for the test run to complete.
> Unfortunately there seems to be no chance to save the money using Xen with
> harddisc emulated physical RAM, right?
Why can''t you configure the Guest OS to have the swap file?  If
swapping at
the Guest Domains doesn''t work, there is no way that swapping at the
hypervisor level will work.  The user process shouldn''t really care how
much
physical ram is there, just if the OS can give it more memory.

I think you need to rethink your numbers and what is expensive and what is
not.  Tests that run for the better portion of a year waiting for results
seem pretty expensive as well, especially as it probably would take a couple
of attempts to get it working correctly. :)

	-Sean

-- 
__________________________________________________________________

Sean Dague                                       Mid-Hudson Valley
sean at dague dot net                            Linux Users Group
http://dague.net                                 http://mhvlug.org

There is no silver bullet.  Plus, werewolves make better neighbors
than zombies, and they tend to keep the vampire population down.
__________________________________________________________________


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

>I''m still really confused here.  How damn slow can it be?  If you
have an
>application that thinks it is in full memory (and needs full memory), and
it
>isn''t, then you''ll probably see in the neighborhood of a
1000 x slow down
>(or worse).  So an operation that normally takes 1 second, would instead 20
>minutes.
That''s somehow to ''easy calculated''. I think that if
our application needs
about 1sec for a query on a non-clustered-memory system (only using standard
mysql harddisc files), then it won''t take 20min on a mysql-cluster with
hard-
drive emulated memory. Why should it? It then would use the same technology
to
store and query data from (in both cases hard-drive) perhaps needing some
more 
time to execute because of some overhead mysql-cluster daemon generates -
but
that''s all. Your calculation seems somehow nonsens to me (sorry!).


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

If you want to force MySQL to use swap in place of physical memory, why 
not just find the place in the source where it checks for physical (vs 
virtual) memory and modify it to require only that adequate virtual 
memory be available?

Using virtual memory without the knowledge of the underlying OS is just 
a really, really, really bad idea. In-memory pages get rewritten 
*exceedingly* frequently in a great many cases -- unlike pages which the 
OS intelligently chooses to swap out, which are selected *because 
they''re not frequently used*. If you''re doing this behind the
OS''s back
-- just mapping a big region of "physical memory" to disk -- then you
no
longer have any of those algorithms working in your favor, and the wait 
times will be *huge*.

As the other respondants have suggested -- don''t do it this way. Modify
MySQL instead.


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

> If you want to force MySQL to use swap in place of physical memory, why
> not just find the place in the source where it checks for physical (vs
> virtual) memory and modify it to require only that adequate virtual
> memory be available?
I must admit that I am not such a crack programmer, but I think that you
can be sure, that changing such a thing will cost more time/money, then
just investing in hardware. Even if it would only take a day to fix this
(I think that it wouldn''t be enough to just comment in a simple if
statement but that this check is made at several stages and that all
other code relies on the fact that the check was made and successful),
this time would cost more money then just buying the RAM.

Anyway - I think that modifying the sources is generally a bad thing -
the whole idea that stands behind testing the application is, that it
should give us a hint, if it can run on a mysql-cluster backend. So if
we modify something in mysql-cluster, results would be worth nothing
because on the live systems we would run with an unmodified version of it.

But I think I''ve got the point, that this won''t work (at least
not with
Xen and perhaps not with any other VM) and we will have to invest in
hardware.

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