Re: KSM not working on 2.6.28.7 and qemu-kvm 0.12.2 ?

Re: KSM not working on 2.6.28.7 and qemu-kvm 0.12.2 ?

[Nikola Ciprich]

Hi Gilles, maybe You have the same problem I experienced?
see http://www.mail-archive.com/kvm@vger.kernel.org/msg28572.html
nik

On Sun, Feb 21, 2010 at 10:35:06PM +0100, Gilles PIETRI wrote:
> Hi,
> 
> I'm running a 2.6.32.7 kernel with KSM enabled (CONFIG_KSM=y), with
> qemu-kvm 0.12.2 that has support for KSM (exec.c checks for
> MADV_MERGEABLE)..
> 
> So I have KSM running, /sys/kernel/mm/ksm/run is at 1, and after a
> few hours running a dozen of VMs, many of them running the same
> OS/base image, I see no page being shared, KSM seems inactive.
> 
> Values are pretty much to their default value, and it seems KSM is
> simply not working.. I see ksmd in the process list though, but here
> are the sysfs values reported:
> ==> /sys/kernel/mm/ksm/full_scans <==
> 0
> 
> ==> /sys/kernel/mm/ksm/max_kernel_pages <==
> 1027257
> 
> ==> /sys/kernel/mm/ksm/pages_shared <==
> 0
> 
> ==> /sys/kernel/mm/ksm/pages_sharing <==
> 0
> 
> ==> /sys/kernel/mm/ksm/pages_to_scan <==
> 100
> 
> ==> /sys/kernel/mm/ksm/pages_unshared <==
> 0
> 
> ==> /sys/kernel/mm/ksm/pages_volatile <==
> 0
> 
> ==> /sys/kernel/mm/ksm/run <==
> 1
> 
> ==> /sys/kernel/mm/ksm/sleep_millisecs <==
> 20
> 
> Any clues?
> 
> Cheers,
> Gilou
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

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Re: KSM not working on 2.6.28.7 and qemu-kvm 0.12.2 ?

[Gilles PIETRI]

Le 22/02/2010 06:40, Nikola Ciprich a écrit :
> Hi Gilles, maybe You have the same problem I experienced?
> see http://www.mail-archive.com/kvm@vger.kernel.org/msg28572.html
> nik
> 

Hi,

The linux headers do include the MADV_MERGEABLE settings, and the libc 
is the debian one which happened to work fine earlier in this regard. 
Anyway I still added the flags just to make sure, and nothing more happens.

Cheers,

Gilou

> On Sun, Feb 21, 2010 at 10:35:06PM +0100, Gilles PIETRI wrote:
>> Hi,
>>
>> I'm running a 2.6.32.7 kernel with KSM enabled (CONFIG_KSM=y), with
>> qemu-kvm 0.12.2 that has support for KSM (exec.c checks for
>> MADV_MERGEABLE)..
>>
>> So I have KSM running, /sys/kernel/mm/ksm/run is at 1, and after a
>> few hours running a dozen of VMs, many of them running the same
>> OS/base image, I see no page being shared, KSM seems inactive.
>>
>> Values are pretty much to their default value, and it seems KSM is
>> simply not working.. I see ksmd in the process list though, but here
>> are the sysfs values reported:
>> ==> /sys/kernel/mm/ksm/full_scans <==
>> 0
>>
>> ==> /sys/kernel/mm/ksm/max_kernel_pages <==
>> 1027257
>>
>> ==> /sys/kernel/mm/ksm/pages_shared <==
>> 0
>>
>> ==> /sys/kernel/mm/ksm/pages_sharing <==
>> 0
>>
>> ==> /sys/kernel/mm/ksm/pages_to_scan <==
>> 100
>>
>> ==> /sys/kernel/mm/ksm/pages_unshared <==
>> 0
>>
>> ==> /sys/kernel/mm/ksm/pages_volatile <==
>> 0
>>
>> ==> /sys/kernel/mm/ksm/run <==
>> 1
>>
>> ==> /sys/kernel/mm/ksm/sleep_millisecs <==
>> 20
>>
>> Any clues?
>>
>> Cheers,
>> Gilou
>> --
>> To unsubscribe from this list: send the line "unsubscribe kvm" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
> 

Re: KSM not working on 2.6.28.7 and qemu-kvm 0.12.2 ?

[Gilles PIETRI]

Le 22/02/2010 22:02, Gilles PIETRI a écrit :
> Le 22/02/2010 06:40, Nikola Ciprich a écrit :
>> Hi Gilles, maybe You have the same problem I experienced?
>> see http://www.mail-archive.com/kvm@vger.kernel.org/msg28572.html
>> nik
>>
> 
> Hi,
> 
> The linux headers do include the MADV_MERGEABLE settings, and the libc 
> is the debian one which happened to work fine earlier in this regard. 
> Anyway I still added the flags just to make sure, and nothing more happens.
> 
> Cheers,
> 
> Gilou

OK, I had a doubt, so I did it again, and made sure there wasn't a 
chance for the MADV_* to be missing... And it was the issue actually.. 
Not sure what happened there, given the linux headers are here.. It 
works fine finally, thanks Nikola for your pointer.

Regards,

Gilou

> 
>> On Sun, Feb 21, 2010 at 10:35:06PM +0100, Gilles PIETRI wrote:
>>> Hi,
>>>
>>> I'm running a 2.6.32.7 kernel with KSM enabled (CONFIG_KSM=y), with
>>> qemu-kvm 0.12.2 that has support for KSM (exec.c checks for
>>> MADV_MERGEABLE)..
>>>
>>> So I have KSM running, /sys/kernel/mm/ksm/run is at 1, and after a
>>> few hours running a dozen of VMs, many of them running the same
>>> OS/base image, I see no page being shared, KSM seems inactive.
>>>
>>> Values are pretty much to their default value, and it seems KSM is
>>> simply not working.. I see ksmd in the process list though, but here
>>> are the sysfs values reported:
>>> ==> /sys/kernel/mm/ksm/full_scans <==
>>> 0
>>>
>>> ==> /sys/kernel/mm/ksm/max_kernel_pages <==
>>> 1027257
>>>
>>> ==> /sys/kernel/mm/ksm/pages_shared <==
>>> 0
>>>
>>> ==> /sys/kernel/mm/ksm/pages_sharing <==
>>> 0
>>>
>>> ==> /sys/kernel/mm/ksm/pages_to_scan <==
>>> 100
>>>
>>> ==> /sys/kernel/mm/ksm/pages_unshared <==
>>> 0
>>>
>>> ==> /sys/kernel/mm/ksm/pages_volatile <==
>>> 0
>>>
>>> ==> /sys/kernel/mm/ksm/run <==
>>> 1
>>>
>>> ==> /sys/kernel/mm/ksm/sleep_millisecs <==
>>> 20
>>>
>>> Any clues?
>>>
>>> Cheers,
>>> Gilou
>>> -- 
>>> To unsubscribe from this list: send the line "unsubscribe kvm" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>
>>
> 
>