[libvirt] [RFC] memory settings interface for containers

[Nikolay Shirokovskiy]

On 13.11.2015 13:55, Dmitry Guryanov wrote:
> On Thu, 2015-11-12 at 11:11 +0300, Nikolay Shirokovskiy wrote:
>> Hi, everyone.
>>
>> I plan to add means to configure vz containers memory setting and have trouble
>> getting it done thru libvirt interface. Looks like current interface fits good
>> for vm memory managment but its not clear how to use it with containers. First
>> let's take aside memory hotplugging which is obviously not suitable for
>> containers. Then memory interface is represented by 2 parameters: total_memory
>> and cur_balloon. For VMs total_memory can't be changed at runtime, cur_ballon
>> can't be greater than total_memory. But for containers memory model is
>> different. We have only one parameter and it can be changed for running 
>> domains.
> 
> Not only one parameter, there are a lot of parameters, that can be tuned with
> memory cgroup. But at least physical pages limit (memory.limit_in_bytes) and
> swap pages (memory.memsw.limit_in_bytes) have sense.
>  
>>  So question is how to map this model to existing interface (it is
>> unlikely to have a new interface for this case). I plan to make both
>> parameters
>> to have same meaning and be equal for containers and update virsh, API and xml
>> model documentation accordingly.
>>
>> I'd be happy to hear core developers opinions on this topic.

Have any ideas?