Confirm understanding about qemu stable API for throttle-group creation

[Chun Feng Wu]

Hi,

 

I noticed there’re different ways to create throttle group based on doc: https://github.com/qemu/qemu/blob/master/docs/throttle.txt
Option 1: through QMP “object-add”
Option 2: through “-object”

 

Based on the info(the following section I pasted) described in doc, my understanding is option1 is stable way to create throttle-group while option2 is not,  am I correct? Any confirmation would be appreciated!

 

“

A group can be created using the object-add QMP function:

 

   { "execute": "object-add",

     "arguments": {

       "qom-type": "throttle-group",

       "id": "group0",

       "limits" : {

         "iops-total": 1000,

         "bps-write": 2097152

       }

     }

   }

 

throttle-group has a 'limits' property (of type ThrottleLimits as

defined in qapi/block-core.json) which can be set on creation or later

with 'qom-set'.

 

A throttle-group can also be created with the -object command line

option but at the moment there is no way to pass a 'limits' parameter

that contains a ThrottleLimits structure. The solution is to set the

individual values directly, like in this example:

 

   -object throttle-group,id=group0,x-iops-total=1000,x-bps-write=2097152

 

Note however that this is not a stable API (hence the 'x-' prefixes) and

will disappear when -object gains support for structured options and

enables use of 'limits'.

“

 

 

-- 

 

Wu