Xen users - Feb 2006 - Running Xen 2.0 for Counter Strike: Source

I''m running Xen on a dual xeon system at the moment and somehow the
results are a bit less than what i expected. I’ve started to do some
monitoring on it to see how bad it is. you can see for yourself on:
http://core.zokahn.com/cs-01/

I''ve installed Xen 2.0 using the howto in howtoforge:
http://www.howtoforge.com/perfect_xen_setup_debian_ubuntu

This virtual machine is running 2 counter-strike public servers. Games has
always been a fine benchmark tool :-) The fps number should be much
higher. On my home server (a single p4 running lots and lots of stuff) the
reading is 150-200 average untweaked with basic settings.

In the counter strike forums there is word about the kernel hz. They say
the kernel should be configured to 1000hz. fortunately the used 2.6.11.12
kernel has a standard setting of 1000hz. As you can see in the kernel
source: include/i386/param.h. However current readings in cs are more like
hz is set to 250!

Can I expect this to be the same in xen 3.0? Is the default 1000hz 
changed by the Xen patches for the client kernels? Is there any way to
tweak Xen for use with Counter-Strike?

Kind regards,

Bart




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> I''m running Xen on a dual xeon system at the moment and somehow
the
> results are a bit less than what i expected. I’ve started to do some
> monitoring on it to see how bad it is. you can see for yourself on:
> http://core.zokahn.com/cs-01/
>
> I''ve installed Xen 2.0 using the howto in howtoforge:
> http://www.howtoforge.com/perfect_xen_setup_debian_ubuntu
>
> This virtual machine is running 2 counter-strike public servers. Games has
> always been a fine benchmark tool :-) The fps number should be much
> higher. On my home server (a single p4 running lots and lots of stuff) the
> reading is 150-200 average untweaked with basic settings.
Hmmmm.  Sounds like performance is degrading badly somewhere.  Have you run 
any more basic benchmarks to determine if network / disk are performing as 
they should?

How have you set up the CPU allocation?  Are you pinning the servers to 
different CPUs?  Are you using hyperthreading?

I imagine that CS doesn''t make optimal use of the network from a 
virtualisation PoV, but I''m still a little surpised its that poor.
> In the counter strike forums there is word about the kernel hz. They say
> the kernel should be configured to 1000hz. fortunately the used 2.6.11.12
> kernel has a standard setting of 1000hz. As you can see in the kernel
> source: include/i386/param.h. However current readings in cs are more like
> hz is set to 250!
Nb. I think the kernel HZ value was reduced to 250 in later kernels anyhow.  
The kernel developers seem a bit unsure of what to set it to, or whether 
they''re actually that bothered about it.
> Can I expect this to be the same in xen 3.0?
It''s worth using Xen 3.0 in any case, since it''ll get
performance and bug
fixes that wouldn''t go into 2.0.  Without understanding more of
what''s
causing your problem I can''t be more specific.

Cheers,
Mark

-- 
Dave: Just a question. What use is a unicyle with no seat?  And no pedals!
Mark: To answer a question with a question: What use is a skateboard?
Dave: Skateboards have wheels.
Mark: My wheel has a wheel!

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Mark Williamson wrote:
>> I''m running Xen on a dual xeon system at the moment and
somehow the
>> results are a bit less than what i expected. I’ve started to do some
>> monitoring on it to see how bad it is. you can see for yourself on:
>> http://core.zokahn.com/cs-01/
>>
>> I''ve installed Xen 2.0 using the howto in howtoforge:
>> http://www.howtoforge.com/perfect_xen_setup_debian_ubuntu
>>
>> This virtual machine is running 2 counter-strike public servers. Games
has
>> always been a fine benchmark tool :-) The fps number should be much
>> higher. On my home server (a single p4 running lots and lots of stuff)
the
>> reading is 150-200 average untweaked with basic settings.
>>     
>   
Can you provide more actual numbers?

With two servers running, I would not expect anything more than 60fps on 
each. Remember, you''re running two (three?) full operating systems with
two full counter strike servers.

Regards,

Anhtony Liguori
> Hmmmm.  Sounds like performance is degrading badly somewhere.  Have you run
> any more basic benchmarks to determine if network / disk are performing as 
> they should?
>
> How have you set up the CPU allocation?  Are you pinning the servers to 
> different CPUs?  Are you using hyperthreading?
>
> I imagine that CS doesn''t make optimal use of the network from a 
> virtualisation PoV, but I''m still a little surpised its that poor.
>
>   
>> In the counter strike forums there is word about the kernel hz. They
say
>> the kernel should be configured to 1000hz. fortunately the used
2.6.11.12
>> kernel has a standard setting of 1000hz. As you can see in the kernel
>> source: include/i386/param.h. However current readings in cs are more
like
>> hz is set to 250!
>>     
>
> Nb. I think the kernel HZ value was reduced to 250 in later kernels anyhow.
> The kernel developers seem a bit unsure of what to set it to, or whether 
> they''re actually that bothered about it.
>
>   
>> Can I expect this to be the same in xen 3.0?
>>     
>
> It''s worth using Xen 3.0 in any case, since it''ll get
performance and bug
> fixes that wouldn''t go into 2.0.  Without understanding more of
what''s
> causing your problem I can''t be more specific.
>
> Cheers,
> Mark
>
>   

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http://lists.xensource.com/xen-users

> Can you provide more actual numbers?
>
> With two servers running, I would not expect anything more than 60fps on
> each. Remember, you''re running two (three?) full operating systems
with
> two full counter strike servers.
But he does have 2 Xeons in the Xen box....   It''d be highly useful to
know
how fast they are though.

Cheers,
Mark
> Regards,
>
> Anhtony Liguori
>
> > Hmmmm.  Sounds like performance is degrading badly somewhere.  Have
you
> > run any more basic benchmarks to determine if network / disk are
> > performing as they should?
> >
> > How have you set up the CPU allocation?  Are you pinning the servers
to
> > different CPUs?  Are you using hyperthreading?
> >
> > I imagine that CS doesn''t make optimal use of the network
from a
> > virtualisation PoV, but I''m still a little surpised its that
poor.
> >
> >> In the counter strike forums there is word about the kernel hz.
They say
> >> the kernel should be configured to 1000hz. fortunately the used
> >> 2.6.11.12 kernel has a standard setting of 1000hz. As you can see
in the
> >> kernel source: include/i386/param.h. However current readings in
cs are
> >> more like hz is set to 250!
> >
> > Nb. I think the kernel HZ value was reduced to 250 in later kernels
> > anyhow. The kernel developers seem a bit unsure of what to set it to,
or
> > whether they''re actually that bothered about it.
> >
> >> Can I expect this to be the same in xen 3.0?
> >
> > It''s worth using Xen 3.0 in any case, since it''ll
get performance and bug
> > fixes that wouldn''t go into 2.0.  Without understanding more
of what''s
> > causing your problem I can''t be more specific.
> >
> > Cheers,
> > Mark
>
> _______________________________________________
> Xen-users mailing list
> Xen-users@lists.xensource.com
> http://lists.xensource.com/xen-users
-- 
Dave: Just a question. What use is a unicyle with no seat?  And no pedals!
Mark: To answer a question with a question: What use is a skateboard?
Dave: Skateboards have wheels.
Mark: My wheel has a wheel!

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

Why not just recompile the kernels to use 1000hz? I did this to get
another application to work better under xen.

I changed all the values to 1000hz in the following files

./linux-2.6.12-xenU/include/asm-xen/asm/param.h
./xen/include/asm-x86/config.h

Thanks
John

-----Original Message-----
From: xen-users-bounces@lists.xensource.com
[mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Bart van den
Heuvel
Sent: Tuesday, February 14, 2006 9:11 AM
To: xen-users@lists.xensource.com
Subject: [Xen-users] Running Xen 2.0 for Counter Strike: Source

I''m running Xen on a dual xeon system at the moment and somehow the
results are a bit less than what i expected. I''ve started to do some
monitoring on it to see how bad it is. you can see for yourself on:
http://core.zokahn.com/cs-01/

I''ve installed Xen 2.0 using the howto in howtoforge:
http://www.howtoforge.com/perfect_xen_setup_debian_ubuntu

This virtual machine is running 2 counter-strike public servers. Games
has
always been a fine benchmark tool :-) The fps number should be much
higher. On my home server (a single p4 running lots and lots of stuff)
the
reading is 150-200 average untweaked with basic settings.

In the counter strike forums there is word about the kernel hz. They say
the kernel should be configured to 1000hz. fortunately the used
2.6.11.12
kernel has a standard setting of 1000hz. As you can see in the kernel
source: include/i386/param.h. However current readings in cs are more
like
hz is set to 250!

Can I expect this to be the same in xen 3.0? Is the default 1000hz 
changed by the Xen patches for the client kernels? Is there any way to
tweak Xen for use with Counter-Strike?

Kind regards,

Bart




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



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

I have recompiled the kernels, both dom0 and domU. Counterstrike comes in
a compiled form (silly enterprises still do that :-)

All is wel and i got the change to compile in the bigmem option! So i''m
very happy there. I can now use more mem for my virtual servers... But
thats where the happyness stops!

Instead of a performance upgrade fps is now steady on 1, so the 1000 hz
options made the fps value go from 50 to 1 instead of a higher value.

I''m running like this for a few hours... Maybe more inspiration will
come
to me.

Regards,

Bart

> Why not just recompile the kernels to use 1000hz? I did this to get
> another application to work better under xen.
>
> I changed all the values to 1000hz in the following files
>
> ./linux-2.6.12-xenU/include/asm-xen/asm/param.h
> ./xen/include/asm-x86/config.h
>
> Thanks
> John
>
> -----Original Message-----
> From: xen-users-bounces@lists.xensource.com
> [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Bart van den
> Heuvel
> Sent: Tuesday, February 14, 2006 9:11 AM
> To: xen-users@lists.xensource.com
> Subject: [Xen-users] Running Xen 2.0 for Counter Strike: Source
>
> I''m running Xen on a dual xeon system at the moment and somehow
the
> results are a bit less than what i expected. I''ve started to do
some
> monitoring on it to see how bad it is. you can see for yourself on:
> http://core.zokahn.com/cs-01/
>
> I''ve installed Xen 2.0 using the howto in howtoforge:
> http://www.howtoforge.com/perfect_xen_setup_debian_ubuntu
>
> This virtual machine is running 2 counter-strike public servers. Games
> has
> always been a fine benchmark tool :-) The fps number should be much
> higher. On my home server (a single p4 running lots and lots of stuff)
> the
> reading is 150-200 average untweaked with basic settings.
>
> In the counter strike forums there is word about the kernel hz. They say
> the kernel should be configured to 1000hz. fortunately the used
> 2.6.11.12
> kernel has a standard setting of 1000hz. As you can see in the kernel
> source: include/i386/param.h. However current readings in cs are more
> like
> hz is set to 250!
>
> Can I expect this to be the same in xen 3.0? Is the default 1000hz
> changed by the Xen patches for the client kernels? Is there any way to
> tweak Xen for use with Counter-Strike?
>
> Kind regards,
>
> Bart
>
>
>
>
> _______________________________________________
> 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
>


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http://lists.xensource.com/xen-users

On Wednesday 15 February 2006 10:37, Bart van den Heuvel
wrote:
> I have recompiled the kernels, both dom0 and domU. Counterstrike comes in
> a compiled form (silly enterprises still do that :-)
>
> All is wel and i got the change to compile in the bigmem option! So
i''m
> very happy there. I can now use more mem for my virtual servers... But
> thats where the happyness stops!
>
> Instead of a performance upgrade fps is now steady on 1, so the 1000 hz
> options made the fps value go from 50 to 1 instead of a higher value.
>
> I''m running like this for a few hours... Maybe more inspiration
will come
> to me.
>
The HZ Value sets how often timer interrups occur, so instead of interrupting 
work 250 times a second, you now interrupt it 1000 times.

I guess timer interrupts in xen are more expensive than on plain linux, since 
they also involve the hypervisor (correct me if I''m wrong here)

if three domains use the same cpu, xen needs to switch the running domain 3000 
times a second, I guess you waste a lot of cycles there.

Another reason (wild guess) could be: the hypervisor still generates 
interrupts at 250HZ, but now the domU kernel now expects them coming at 
1000Hz, hence the internal timing of the kernel is way off, resulting of the 
timing source of your CS server working only on full seconds now => 1 frame 
per second max...

For applications requiring short response time, a "lesser"
virtualization
method, like linux-vserver, might provide much better performance.

/Ernst

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

Ernst,

I see what you mean, if your thougts prove to be true than vserver would
be more of an option, i would hate to leave xen the concept is very
attractive.

Now that i look at my graphs again I see a very different picture!

Please check http://core.zokahn.com/cs-01/

FPS is way up! I must be going MAD....

Thanks!

Bart
> On Wednesday 15 February 2006 10:37, Bart van den Heuvel wrote:
>> I have recompiled the kernels, both dom0 and domU. Counterstrike comes
>> in
>> a compiled form (silly enterprises still do that :-)
>>
>> All is wel and i got the change to compile in the bigmem option! So
i''m
>> very happy there. I can now use more mem for my virtual servers... But
>> thats where the happyness stops!
>>
>> Instead of a performance upgrade fps is now steady on 1, so the 1000 hz
>> options made the fps value go from 50 to 1 instead of a higher value.
>>
>> I''m running like this for a few hours... Maybe more
inspiration will
>> come
>> to me.
>>
> The HZ Value sets how often timer interrups occur, so instead of
> interrupting
> work 250 times a second, you now interrupt it 1000 times.
>
> I guess timer interrupts in xen are more expensive than on plain linux,
> since
> they also involve the hypervisor (correct me if I''m wrong here)
>
> if three domains use the same cpu, xen needs to switch the running domain
> 3000
> times a second, I guess you waste a lot of cycles there.
>
> Another reason (wild guess) could be: the hypervisor still generates
> interrupts at 250HZ, but now the domU kernel now expects them coming at
> 1000Hz, hence the internal timing of the kernel is way off, resulting of
> the
> timing source of your CS server working only on full seconds now => 1
> frame
> per second max...
>
> For applications requiring short response time, a "lesser"
virtualization
> method, like linux-vserver, might provide much better performance.
>
> /Ernst
>
> _______________________________________________
> Xen-users mailing list
> Xen-users@lists.xensource.com
> http://lists.xensource.com/xen-users
>


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

Did you change anything else to get this or only to 1000HZ?

John

-----Original Message-----
From: xen-users-bounces@lists.xensource.com
[mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Bart van den
Heuvel
Sent: Wednesday, February 15, 2006 6:17 AM
To: Ernst Bachmann
Cc: xen-users@lists.xensource.com
Subject: Re: [Xen-users] Running Xen 2.0 for Counter Strike: Source

Ernst,

I see what you mean, if your thougts prove to be true than vserver would
be more of an option, i would hate to leave xen the concept is very
attractive.

Now that i look at my graphs again I see a very different picture!

Please check http://core.zokahn.com/cs-01/

FPS is way up! I must be going MAD....

Thanks!

Bart
> On Wednesday 15 February 2006 10:37, Bart van den Heuvel wrote:
>> I have recompiled the kernels, both dom0 and domU. Counterstrike
comes
>> in
>> a compiled form (silly enterprises still do that :-)
>>
>> All is wel and i got the change to compile in the bigmem option! So
i''m
>> very happy there. I can now use more mem for my virtual servers...
But
>> thats where the happyness stops!
>>
>> Instead of a performance upgrade fps is now steady on 1, so the 1000
hz
>> options made the fps value go from 50 to 1 instead of a higher value.
>>
>> I''m running like this for a few hours... Maybe more
inspiration will
>> come
>> to me.
>>
> The HZ Value sets how often timer interrups occur, so instead of
> interrupting
> work 250 times a second, you now interrupt it 1000 times.
>
> I guess timer interrupts in xen are more expensive than on plain
linux,
> since
> they also involve the hypervisor (correct me if I''m wrong here)
>
> if three domains use the same cpu, xen needs to switch the running
domain
> 3000
> times a second, I guess you waste a lot of cycles there.
>
> Another reason (wild guess) could be: the hypervisor still generates
> interrupts at 250HZ, but now the domU kernel now expects them coming
at
> 1000Hz, hence the internal timing of the kernel is way off, resulting
of
> the
> timing source of your CS server working only on full seconds now => 1
> frame
> per second max...
>
> For applications requiring short response time, a "lesser"
virtualization
> method, like linux-vserver, might provide much better performance.
>
> /Ernst
>
> _______________________________________________
> Xen-users mailing list
> Xen-users@lists.xensource.com
> http://lists.xensource.com/xen-users
>


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http://lists.xensource.com/xen-users



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http://lists.xensource.com/xen-users

Only changed the 100 hz setting to 1000 hz and turned Big mem support
(4gb) on for both the dom0 and domU kernels. I configured the virtual
machine to have 1000mb memory, it only used 830 meg or so without the big
mem option.
That''s viseble in the graph at the bottom of
http://core.zokahn.com/cs-01/

75 fps is not a big deal! other systems run with 200 - 500 fps but it''s
a
start! And if my players are happy...

I will still try and boot to a normal debian kernel and run the same
gameservers (they can run on the same machine) and test the difference
between the Xen and the Normal world.

Gr,

Bart


> Did you change anything else to get this or only to 1000HZ?
>
> John
>
> -----Original Message-----
> From: xen-users-bounces@lists.xensource.com
> [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Bart van den
Heuvel
> Sent: Wednesday, February 15, 2006 6:17 AM
> To: Ernst Bachmann
> Cc: xen-users@lists.xensource.com
> Subject: Re: [Xen-users] Running Xen 2.0 for Counter Strike: Source
>
> Ernst,
>
> I see what you mean, if your thougts prove to be true than vserver would
be more of an option, i would hate to leave xen the concept is very
attractive.
>
> Now that i look at my graphs again I see a very different picture!
>
> Please check http://core.zokahn.com/cs-01/
>
> FPS is way up! I must be going MAD....
>
> Thanks!
>
> Bart
>
>> On Wednesday 15 February 2006 10:37, Bart van den Heuvel wrote:
>>> I have recompiled the kernels, both dom0 and domU. Counterstrike
> comes
>>> in
>>> a compiled form (silly enterprises still do that :-)
>>>
>>> All is wel and i got the change to compile in the bigmem option! So
> i''m
>>> very happy there. I can now use more mem for my virtual servers...
> But
>>> thats where the happyness stops!
>>>
>>> Instead of a performance upgrade fps is now steady on 1, so the
1000
> hz
>>> options made the fps value go from 50 to 1 instead of a higher
value.
>>>
>>> I''m running like this for a few hours... Maybe more
inspiration will come
>>> to me.
>>>
>> The HZ Value sets how often timer interrups occur, so instead of
interrupting
>> work 250 times a second, you now interrupt it 1000 times.
>>
>> I guess timer interrupts in xen are more expensive than on plain
> linux,
>> since
>> they also involve the hypervisor (correct me if I''m wrong
here)
>>
>> if three domains use the same cpu, xen needs to switch the running
> domain
>> 3000
>> times a second, I guess you waste a lot of cycles there.
>>
>> Another reason (wild guess) could be: the hypervisor still generates
interrupts at 250HZ, but now the domU kernel now expects them
coming
> at
>> 1000Hz, hence the internal timing of the kernel is way off, resulting
> of
>> the
>> timing source of your CS server working only on full seconds now =>
1
frame
>> per second max...
>>
>> For applications requiring short response time, a "lesser"
> virtualization
>> method, like linux-vserver, might provide much better performance.
>>
>> /Ernst
>>
>> _______________________________________________
>> 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
>




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Why don''t you try xen3? Even if there is no performance benefit, it
would help
you to stay up2date with the recent development. But maybe even xen3 solves 
some performance issues without the need for further tweaking.

you are using debian? I would suggest taking a look at the following post:
http://lists.xensource.com/archives/html/xen-users/2006-01/msg00641.html

--Ralph

Am Mittwoch, 15. Februar 2006 14:40 schrieb Bart van den
Heuvel:
> Only changed the 100 hz setting to 1000 hz and turned Big mem support
> (4gb) on for both the dom0 and domU kernels. I configured the virtual
> machine to have 1000mb memory, it only used 830 meg or so without the big
> mem option.
> That''s viseble in the graph at the bottom of
http://core.zokahn.com/cs-01/
>
> 75 fps is not a big deal! other systems run with 200 - 500 fps but
it''s a
> start! And if my players are happy...
>
> I will still try and boot to a normal debian kernel and run the same
> gameservers (they can run on the same machine) and test the difference
> between the Xen and the Normal world.
>
> Gr,
>
> Bart
>
> > Did you change anything else to get this or only to 1000HZ?
> >
> > John
> >
> > -----Original Message-----
> > From: xen-users-bounces@lists.xensource.com
> > [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Bart van
den
>
> Heuvel
>
> > Sent: Wednesday, February 15, 2006 6:17 AM
> > To: Ernst Bachmann
> > Cc: xen-users@lists.xensource.com
> > Subject: Re: [Xen-users] Running Xen 2.0 for Counter Strike: Source
> >
> > Ernst,
> >
> > I see what you mean, if your thougts prove to be true than vserver
would
>
> be more of an option, i would hate to leave xen the concept is very
> attractive.
>
> > Now that i look at my graphs again I see a very different picture!
> >
> > Please check http://core.zokahn.com/cs-01/
> >
> > FPS is way up! I must be going MAD....
> >
> > Thanks!
> >
> > Bart
> >
> >> On Wednesday 15 February 2006 10:37, Bart van den Heuvel wrote:
> >>> I have recompiled the kernels, both dom0 and domU.
Counterstrike
> >
> > comes
> >
> >>> in
> >>> a compiled form (silly enterprises still do that :-)
> >>>
> >>> All is wel and i got the change to compile in the bigmem
option! So
> >
> > i''m
> >
> >>> very happy there. I can now use more mem for my virtual
servers...
> >
> > But
> >
> >>> thats where the happyness stops!
> >>>
> >>> Instead of a performance upgrade fps is now steady on 1, so
the 1000
> >
> > hz
> >
> >>> options made the fps value go from 50 to 1 instead of a higher
value.
> >>>
> >>> I''m running like this for a few hours... Maybe more
inspiration will
> >>> come to me.
> >>
> >> The HZ Value sets how often timer interrups occur, so instead of
>
> interrupting
>
> >> work 250 times a second, you now interrupt it 1000 times.
> >>
> >> I guess timer interrupts in xen are more expensive than on plain
> >
> > linux,
> >
> >> since
> >> they also involve the hypervisor (correct me if I''m wrong
here)
> >>
> >> if three domains use the same cpu, xen needs to switch the running
> >
> > domain
> >
> >> 3000
> >> times a second, I guess you waste a lot of cycles there.
> >>
> >> Another reason (wild guess) could be: the hypervisor still
generates
>
> interrupts at 250HZ, but now the domU kernel now expects them coming
>
> > at
> >
> >> 1000Hz, hence the internal timing of the kernel is way off,
resulting
> >
> > of
> >
> >> the
> >> timing source of your CS server working only on full seconds now
=> 1
>
> frame
>
> >> per second max...
> >>
> >> For applications requiring short response time, a
"lesser"
> >
> > virtualization
> >
> >> method, like linux-vserver, might provide much better performance.
> >>
> >> /Ernst
> >>
> >> _______________________________________________
> >> 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
>
> _______________________________________________
> 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

The choice for Xen 2 was mostly because of a network issue discussed in
this list some time ago (by Falko Timme). I believe this issue is still
open.
http://lists.xensource.com/archives/html/xen-users/2006-01/msg00504.html

I have a question open in this list about upgrading. I would like to give
3 a go offcourse. However i would hate the idea to do a complete clean
reinstall of Debian. Is there somekind of hint on upgrading from 2 to 3?
Using the .deb packages i figure that i would just move all the 2.0 stuff
of the system and install the .deb packs overwriting the prior install of
2.0.8 from source.

Hahaa lots of questions :-)

Gr,

Bart


> Why don''t you try xen3? Even if there is no performance benefit,
it would
> help
> you to stay up2date with the recent development. But maybe even xen3
> solves
> some performance issues without the need for further tweaking.
>
> you are using debian? I would suggest taking a look at the following post:
> http://lists.xensource.com/archives/html/xen-users/2006-01/msg00641.html
>
> --Ralph
>
> Am Mittwoch, 15. Februar 2006 14:40 schrieb Bart van den Heuvel:
>> Only changed the 100 hz setting to 1000 hz and turned Big mem support
>> (4gb) on for both the dom0 and domU kernels. I configured the virtual
>> machine to have 1000mb memory, it only used 830 meg or so without the
>> big
>> mem option.
>> That''s viseble in the graph at the bottom of
>> http://core.zokahn.com/cs-01/
>>
>> 75 fps is not a big deal! other systems run with 200 - 500 fps but
it''s
>> a
>> start! And if my players are happy...
>>
>> I will still try and boot to a normal debian kernel and run the same
>> gameservers (they can run on the same machine) and test the difference
>> between the Xen and the Normal world.
>>
>> Gr,
>>
>> Bart
>>
>> > Did you change anything else to get this or only to 1000HZ?
>> >
>> > John
>> >
>> > -----Original Message-----
>> > From: xen-users-bounces@lists.xensource.com
>> > [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Bart
van
>> den
>>
>> Heuvel
>>
>> > Sent: Wednesday, February 15, 2006 6:17 AM
>> > To: Ernst Bachmann
>> > Cc: xen-users@lists.xensource.com
>> > Subject: Re: [Xen-users] Running Xen 2.0 for Counter Strike:
Source
>> >
>> > Ernst,
>> >
>> > I see what you mean, if your thougts prove to be true than vserver
>> would
>>
>> be more of an option, i would hate to leave xen the concept is very
>> attractive.
>>
>> > Now that i look at my graphs again I see a very different picture!
>> >
>> > Please check http://core.zokahn.com/cs-01/
>> >
>> > FPS is way up! I must be going MAD....
>> >
>> > Thanks!
>> >
>> > Bart
>> >
>> >> On Wednesday 15 February 2006 10:37, Bart van den Heuvel
wrote:
>> >>> I have recompiled the kernels, both dom0 and domU.
Counterstrike
>> >
>> > comes
>> >
>> >>> in
>> >>> a compiled form (silly enterprises still do that :-)
>> >>>
>> >>> All is wel and i got the change to compile in the bigmem
option! So
>> >
>> > i''m
>> >
>> >>> very happy there. I can now use more mem for my virtual
servers...
>> >
>> > But
>> >
>> >>> thats where the happyness stops!
>> >>>
>> >>> Instead of a performance upgrade fps is now steady on 1,
so the 1000
>> >
>> > hz
>> >
>> >>> options made the fps value go from 50 to 1 instead of a
higher
>> value.
>> >>>
>> >>> I''m running like this for a few hours... Maybe
more inspiration will
>> >>> come to me.
>> >>
>> >> The HZ Value sets how often timer interrups occur, so instead
of
>>
>> interrupting
>>
>> >> work 250 times a second, you now interrupt it 1000 times.
>> >>
>> >> I guess timer interrupts in xen are more expensive than on
plain
>> >
>> > linux,
>> >
>> >> since
>> >> they also involve the hypervisor (correct me if I''m
wrong here)
>> >>
>> >> if three domains use the same cpu, xen needs to switch the
running
>> >
>> > domain
>> >
>> >> 3000
>> >> times a second, I guess you waste a lot of cycles there.
>> >>
>> >> Another reason (wild guess) could be: the hypervisor still
generates
>>
>> interrupts at 250HZ, but now the domU kernel now expects them coming
>>
>> > at
>> >
>> >> 1000Hz, hence the internal timing of the kernel is way off,
resulting
>> >
>> > of
>> >
>> >> the
>> >> timing source of your CS server working only on full seconds
now => 1
>>
>> frame
>>
>> >> per second max...
>> >>
>> >> For applications requiring short response time, a
"lesser"
>> >
>> > virtualization
>> >
>> >> method, like linux-vserver, might provide much better
performance.
>> >>
>> >> /Ernst
>> >>
>> >> _______________________________________________
>> >> 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
>>
>> _______________________________________________
>> 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

Am Mittwoch, 15. Februar 2006 15:58 schrieb Bart van den
Heuvel:
> The choice for Xen 2 was mostly because of a network issue discussed in
> this list some time ago (by Falko Timme). I believe this issue is still
> open.
> http://lists.xensource.com/archives/html/xen-users/2006-01/msg00504.html
don''t know, never experience something like that on my xen3 debian
machines.
> I have a question open in this list about upgrading. I would like to give
> 3 a go offcourse. However i would hate the idea to do a complete clean
> reinstall of Debian.
That shouldn''t be needed in the most cases.
> Is there somekind of hint on upgrading from 2 to 3? 
> Using the .deb packages i figure that i would just move all the 2.0 stuff
> of the system and install the .deb packs overwriting the prior install of
> 2.0.8 from source.
yes, you should remove all old 2.0 stuff from your system and then install the 
xen3 packages. typing "apt-get install xen" should be enough if you
have
added the correct lines to your sources.list.

then if you want to compile your own kernel I would suggest taking a look at:
 http://www.debian-administration.org/articles/320

otherwise also install the "linux-xen0-2.6" package. there will be
some hints
that gets shown on installation. just the regular stuff like updating
grub''s
menu.list, generating an initrd and copying the modules to the domU 
filesystems.

that should be all... if you want to downgrade again, then you would have to 
remove the packages again and install old 2.0.7 or 2.0.8 packages (or 
recompile it from source again).

there are just some things that have really changes. I think "xen-br0"
was the
default bridge name in xen2 and in xen3 it''s "xenbr0". Also
you shouldn''t use
"nics = X" and the vcpu/cpu syntax has changed a bit. I think
that''s it.
> Hahaa lots of questions :-)
If you don''t want to compile your own kernel for xen3, then I guess
upgrading
is not taking as long as if you just would recompile your xen2 kernel 
again :)
>
> Gr,
>
> Bart
>
> > Why don''t you try xen3? Even if there is no performance
benefit, it would
> > help
> > you to stay up2date with the recent development. But maybe even xen3
> > solves
> > some performance issues without the need for further tweaking.
> >
> > you are using debian? I would suggest taking a look at the following
> > post:
> >
http://lists.xensource.com/archives/html/xen-users/2006-01/msg00641.html
> >
> > --Ralph
> >
> > Am Mittwoch, 15. Februar 2006 14:40 schrieb Bart van den Heuvel:
> >> Only changed the 100 hz setting to 1000 hz and turned Big mem
support
> >> (4gb) on for both the dom0 and domU kernels. I configured the
virtual
> >> machine to have 1000mb memory, it only used 830 meg or so without
the
> >> big
> >> mem option.
> >> That''s viseble in the graph at the bottom of
> >> http://core.zokahn.com/cs-01/
> >>
> >> 75 fps is not a big deal! other systems run with 200 - 500 fps but
it''s
> >> a
> >> start! And if my players are happy...
> >>
> >> I will still try and boot to a normal debian kernel and run the
same
> >> gameservers (they can run on the same machine) and test the
difference
> >> between the Xen and the Normal world.
> >>
> >> Gr,
> >>
> >> Bart
> >>
> >> > Did you change anything else to get this or only to 1000HZ?
> >> >
> >> > John
> >> >
> >> > -----Original Message-----
> >> > From: xen-users-bounces@lists.xensource.com
> >> > [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of
Bart van
> >>
> >> den
> >>
> >> Heuvel
> >>
> >> > Sent: Wednesday, February 15, 2006 6:17 AM
> >> > To: Ernst Bachmann
> >> > Cc: xen-users@lists.xensource.com
> >> > Subject: Re: [Xen-users] Running Xen 2.0 for Counter Strike:
Source
> >> >
> >> > Ernst,
> >> >
> >> > I see what you mean, if your thougts prove to be true than
vserver
> >>
> >> would
> >>
> >> be more of an option, i would hate to leave xen the concept is
very
> >> attractive.
> >>
> >> > Now that i look at my graphs again I see a very different
picture!
> >> >
> >> > Please check http://core.zokahn.com/cs-01/
> >> >
> >> > FPS is way up! I must be going MAD....
> >> >
> >> > Thanks!
> >> >
> >> > Bart
> >> >
> >> >> On Wednesday 15 February 2006 10:37, Bart van den Heuvel
wrote:
> >> >>> I have recompiled the kernels, both dom0 and domU.
Counterstrike
> >> >
> >> > comes
> >> >
> >> >>> in
> >> >>> a compiled form (silly enterprises still do that :-)
> >> >>>
> >> >>> All is wel and i got the change to compile in the
bigmem option! So
> >> >
> >> > i''m
> >> >
> >> >>> very happy there. I can now use more mem for my
virtual servers...
> >> >
> >> > But
> >> >
> >> >>> thats where the happyness stops!
> >> >>>
> >> >>> Instead of a performance upgrade fps is now steady on
1, so the 1000
> >> >
> >> > hz
> >> >
> >> >>> options made the fps value go from 50 to 1 instead of
a higher
> >>
> >> value.
> >>
> >> >>> I''m running like this for a few hours...
Maybe more inspiration will
> >> >>> come to me.
> >> >>
> >> >> The HZ Value sets how often timer interrups occur, so
instead of
> >>
> >> interrupting
> >>
> >> >> work 250 times a second, you now interrupt it 1000 times.
> >> >>
> >> >> I guess timer interrupts in xen are more expensive than
on plain
> >> >
> >> > linux,
> >> >
> >> >> since
> >> >> they also involve the hypervisor (correct me if
I''m wrong here)
> >> >>
> >> >> if three domains use the same cpu, xen needs to switch
the running
> >> >
> >> > domain
> >> >
> >> >> 3000
> >> >> times a second, I guess you waste a lot of cycles there.
> >> >>
> >> >> Another reason (wild guess) could be: the hypervisor
still generates
> >>
> >> interrupts at 250HZ, but now the domU kernel now expects them
coming
> >>
> >> > at
> >> >
> >> >> 1000Hz, hence the internal timing of the kernel is way
off, resulting
> >> >
> >> > of
> >> >
> >> >> the
> >> >> timing source of your CS server working only on full
seconds now => 1
> >>
> >> frame
> >>
> >> >> per second max...
> >> >>
> >> >> For applications requiring short response time, a
"lesser"
> >> >
> >> > virtualization
> >> >
> >> >> method, like linux-vserver, might provide much better
performance.
> >> >>
> >> >> /Ernst
> >> >>
> >> >> _______________________________________________
> >> >> 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
> >>
> >> _______________________________________________
> >> 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
_______________________________________________
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