Hello Team,

This email is to discuss the implementation details = regarding state sensors association with inventory objects when multipl= e applications are involved.

On our platform, we have a service that populates di= fferent inventory objects like CPU, GPU, Power Supply, Memory, etc.

For example, let’s say there is a CPU instance= that is represented over dbus like below

/xyz/openbmc_project/inventory/system/processors/CPU0

Then we have another application that hosts state se= nsor information related to this CPU0 instance.

To be more specific the second application is the pl= dm daemon which reads all the state sensor information related to this CPU.

These are discrete sensors that are represented usin= g unique dbus interfaces.

Example (dbus interface)

CPU throttle state (xyz.openbmc_project.State.ProcessorPerformance)
CPU power supply reg state (xyz.openbmc_project.State= .Decorator.PowerSystemInputs)

Now in the above case if I must associate the state = sensor (from Pldm) with the inventory object (from a different app) then wh= at would be a preferred way?

My end goal is to get these state sensors over redfi= sh and association will help me identify the relation between the entities = and the sensor data.

Few thoughts which are in my mind

Option 1: Both applica= tions use the exact same dbus object path = ;

App1 :

- /xyz/openbmc_pro= ject/inventory/system/processors/CPU0

&= nbsp; - xyz.openbmc_project.Inventory.Item.Cpu

&nbs= p; App2 (pldmd) :

- /xyz/openbmc_project/inventory/syste= m/processors/CPU0

- xyz.op= enbmc_project.State.ProcessorPerformance

&nbs= p; Bmcweb uses the object mapper to get the o= bject path which implements the required dbus interface and then will ident= ity the CPU0 instance from the object path.

&nbs= p; Option 2: There will be an expli= cit association defined between the inventory object and the state sensor o= bject

App1 :

- /xyz/openbmc_pro= ject/inventory/system/processors/CPU0

&= nbsp; - xyz.openbmc_project.Inventory.Item.Cpu

&= nbsp; - .Associations

&= nbsp; - all_states

&= nbsp; &nbs= p; - /xyz/openbmc_project/State/CPU0_Performance

&nbs= p; App2 (pldmd) :

- /xyz/openbmc_project/State/CPU0_Perf= ormance

- xyz.op= enbmc_project.State.ProcessorPerformance

&nbs= p; New keyword ‘all_states’ = ;is used as an association string.

&nbs= p; Bmcweb will use this association to f= ind the object path of the state sensor which implements the state sensor w= hich belongs to the CPU0 instance.

&nbs= p; This pattern is very similar to how t= he numeric sensor code is working today.

Please provide your thoughts/preferences regarding t= he options.

Comment If there are other ways to solve the same pr= oblem.

Thanks and Regards,

Rohit PAI