Re: Using tools such as ionice inside guests

Emmanuel Lacour
2016-05-20T12:55:03Z

Le 18/05/2016 19:12, Paolo Bonzini a écrit :
>
>
> On 18/05/2016 18:26, Emmanuel Lacour wrote:
>> Thanks, it's a bad news for us :(
>>
>> I will try to play with cgroups io throttling to limit by iops or bytes
>> read, but it'll be a hard limit rather than a priority :(
>
> That probably won't work either, but you can use io throttling on the
> host too.
>

I'll try and let you now if it works. I cannot do this on the host,
because it's per processes inside each VMs, not betweeen VMs.

>> Do you think there could be back some io priority throttling in not so
>> far future kernels?
>
> I wouldn't oppose a patch to add back the non-mq path, but as far as I
> know nobody is working on it. It's not hard and I can help if you need
> guidance.
>
> Adding I/O scheduler support to blk-mq has been promised for at least a
> year now, but I'm not aware of which kernel release might have the work.
> It's not even been submitted to LKML, so I guess it's quite far away.
>

Unfortunatly, I'm a sysadmin with too much little dev knowledge :(