Topic analysis in CPS and NCMP for Capacity Planning
- Priyank Maheshwari
References
CPS Data Notifications Overview
Analysis
Below analysis shows the use case attached to a particular topic. What data is been sent out and by whom.
Have linked the schema used which can be used to estimate the size of the events.
Topic | Use Case | In Use | Event size ( Estimate T Shirt Size ) | Schema | Frequency ( In terms of discovery ) | Notes | |
|---|---|---|---|---|---|---|---|
| 1 | cps.data-updated-events | Cps Core Notifications Possible operations CREATE UPDATE DELETE | Yes ( But only for cached/ non passthrough data ) | Contains only 6 string attributes for now. ( Small ) | 1 event per registration request 1 event per de-registration request additional events if the underlying datanode is updated. | Work in progress to limit the number of notifications based on subscription feature.
Can be individually disabled using a property. | |
| 2 | dmi-device-heartbeat | Trust Level | Feature available but not actively used. | Just contain one attribute that contain the effective trust level from the device. ( Small ) | No data at this moment |
| |
| 3 | subscription | Cm Subscription | Feature available and plans to use it to filter the notifications. | Can vary. Contains attributes that can accept list of data. Depends on the detail of the subscription ( scopeFilter , targetFilter etc )
| Not directly used during discovery. | Part of subscription flow. | |
| 4 | ncmp-dmi-cm-avc-subscription | Cm Subscription | As above. | Depends on the filters present in the incoming subscription request and number of cm handle properties the target filter has.
| Not directly used during discovery. | Part of subscription flow. | |
| 5 | dmi-ncmp-cm-avc-subscription | Cm Subscription | As above. | Just a response if the request was ACCEPTED or REJECTED. | Not directly used during discovery. | Part of subscription flow. | |
| 6 | subscription-response | Cm Subscription | As above. | Contains list of targets that are ACCEPTED, REJECTED or in PENDING state.
| Not directly used during discovery. | Part of subscription flow. | |
| 7 | ncmp-events | Lifecycle Management Events Any state transition happening to the cm handle will result in an event. None(hypothetical ) to ADVISED ADVISED to READY ADVISED to LOCKED LOCKED to ADVISED READY to DELETING DELETING to DELETED | Yes | Contains cm handle state transition , cm handle properties and few other attributes. ( Small to Large ) - depends on the number of properties associated with a cmhandle. | 4 events minimum for the best case for registration and de-registration.
If cm handles go to LOCKED state then the number of events could increase because of internal retry logic. |
|
Note : Event size is categorized in terms of T-Shirt size with respect to the attributes type present in the schema. Eg : for simple object like string then categorizing as Small. For complex objects which can accommodate more number of objects then categorizing as Large.