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Re: About over-commit memory

 

What is the intention of overcommit here?

Is it allowable (possible?) to have a single VM with more RAM allocated than any physical machine?

Or VMs allocated/running that together are more than available RAM?

--
Wolf

On Jun 21, 2012, at 6:13 PM, Vishvananda Ishaya <vishvananda@xxxxxxxxx> wrote:

> I just noticed there is a bug in ram_allocation_ratio, it actually only multiplies the check for free ram which doen't do a lot.  Bug filed here:
> 
> https://bugs.launchpad.net/nova/+bug/1016273
> 
> In the meantime, to overcommit you will have to disable the ram check completely by setting the following set of enabled filters in conf.
> 
> scheduler_default_filters=AvailabilityZoneFilter,ComputeFilter
> 
> Vish
> 
> On Jun 21, 2012, at 3:03 PM, Sam Su wrote:
> 
>> Hi Vish,
>> 
>> Thank you for your response.
>> 
>> I added a 'line ram_allocation_ratio=10' in nova.conf, then restarted nova-scheduler in control node. after that was done, I tried to create a VM, but it still failed, and the debug info is showing as below:
>> http://pastebin.com/RDHb9fDU
>> 
>> Can you help me to take a look at the error info at your convenience?
>> 
>> Thanks,
>> Sam
>> 
>> On Thu, Jun 21, 2012 at 12:23 PM, Vishvananda Ishaya <vishvananda@xxxxxxxxx> wrote:
>> Try setting:
>> 
>> ram_allocation_ratio=10
>> 
>> in your nova.conf (it defaults to 1.5)
>> 
>> Vish
>> 
>> On Jun 21, 2012, at 11:34 AM, Sam Su wrote:
>> 
>>> Hi,
>>> 
>>> I have a mini openstack environment with one compute node and one nova control node. There is 4G memory in the compute node, and I have allocated 2 VMs with 2G memory for each VM. When I try to create another VM , I get the error as below:
>>> http://pastebin.com/QZMQvXtB
>>> 
>>> I am wondering whether Openstack has support memory overcommit? How to do this? 
>>> 
>>> It will be much appreciated If someone can give me some hints about this in convenience.
>>> 
>>> Thanks,
>>> Sam
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>> 
>> 
> 
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