Svc::DpManager (Active Component)

1. Introduction

Svc::DpManager is an active component for managing data products. It does the following:

1. Receive requests for buffers to hold data products.

2. When a client component synchronously requests a data product buffer, request an Fw::Buffer from a buffer manager. Return the buffer to the client component so the component can fill it.

3. When a client component asynchronously requests a data product buffer, request an Fw::Buffer from a buffer manager. Send the buffer to the client component so the component can fill it.

4. Receive buffers filled with data products by client components. Upon receiving a buffer, send the buffer out on a port. Another component such as Svc::BufferAccumulator or Svc::DpWriter will process the buffer and then send it back to the buffer manager for deallocation.

2. Requirements

Requirement	Description	Rationale	Verification Method
SVC-DPMANAGER-001	Svc::DpManager shall provide an array of ports for synchronously requesting and receiving data product buffers.	This capability supports the product get port in the auto-generated code for components that define data products.	Unit test
SVC-DPMANAGER-002	Svc::DpManager shall provide arrays of ports for receiving and asynchronously responding to requests for data product buffers.	This capability supports the product request and product recv ports in the auto-generated code for components that define data products.	Unit test
SVC-DPMANAGER-003	Svc::DpManager shall receive data product buffers and forward them for further processing.	This requirement provides a pass-through capability for sending data product buffers to downstream components. Svc::DpManager receives data product input on a port of type Fw::DpSend. This input consists of a container ID and an Fw::Buffer B. Svc::DpManager sends B on a port of type Fw::BufferSend. This port type is used by the standard F Prime components for managing and logging data, e.g., Svc::BufferAccumulator, Svc::DpWriter.	Unit test
SVC-DPMANAGER-004	Svc::DpManager shall provide telemetry that reports the number of successful allocations, the number of failed allocations, and the volume of data handled.	This requirement establishes the telemetry interface for the component.	Unit test

3. Design

3.1. Component Diagram

The diagram below shows the DpManager component.

3.2. Ports

DpManager has the following ports:

Kind	Name	Port Type	Usage
async input	schedIn	Svc.Sched	Schedule in port
sync input	productGetIn	[DpManagerNumPorts] Fw.DpGet	Ports for responding to a data product get from a client component
async input	productRequestIn	[DpManagerNumPorts] Fw.DpRequest	Ports for receiving data product buffer requests from a client component
output	productResponseOut	[DpManagerNumPorts] Fw.DpResponse	Ports for sending requested data product buffers to a client component
output	bufferGetOut	[DpManagerNumPorts] Fw.BufferGet	Ports for getting buffers from a Buffer Manager
async input	productSendIn	[DpManagerNumPorts] Fw.DpSend	Ports for receiving filled data product buffers from a client component
output	productSendOut	[DpManagerNumPorts] Fw.BufferSend	Ports for sending filled data product buffers to a downstream component
time get	timeGetOut	Fw.Time	Time get port
telemetry	tlmOut	Fw.Tlm	Telemetry port
event	eventOut	Fw.Log	Event port
text event	textEventOut	Fw.LogText	Text event port

3.3. State

DpManager maintains the following state:

1. numSuccessfulAllocations (U32): The number of successful buffer allocations.

2. numFailedAllocations (U32): The number of failed buffer allocations.

3. numDataProducts (U32): The number of data products handled.

4. numBytes (U64): The number of bytes handled.

3.4. Compile-Time Setup

The configuration constant DpManagerNumPorts specifies the number of ports for requesting data product buffers and for sending filled data products.

3.5. Runtime Setup

No special runtime setup is required.

3.6. Port Handlers

3.6.1. schedIn

The handler for this port sends out the state variables as telemetry.

3.6.2. productGetIn

This handler receives a port number portNum, a container ID id, a requested buffer size size, and a mutable reference to a buffer B. It does the following:

1. Set status = getBuffer(portNum, id, size, B).

2. Return status.

3.6.3. productRequestIn

This handler receives a port number portNum, a container ID id and a requested buffer size size. It does the following:

1. Initialize a local variable B with an invalid buffer.

2. Set status = getBuffer(portNum id, size, B).

3. Send (id, B, status) on port portNum of productResponseOut.

3.6.4. productSendIn

This handler receives a port number portNum, a data product ID I and a buffer B. It does the following:

1. Update numDataProducts and numBytes.

2. Send B on port portNum of productSendOut.

3.7. Helper Methods

3.7.1. getBuffer

This function receives a port number portNum, a container ID id, a requested buffer size size, and a mutable reference to a buffer B. It does the following:

1. Set status = FAILURE.

2. Set B = bufferGetOut_out(portNum, size).

3. If B is valid, then atomically increment numSuccessfulAllocations and set status = SUCCESS.

4. Otherwise atomically increment numFailedAllocations and emit a warning event.

5. Return status.

4. Ground Interface

4.1. Commands

Kind	Name	Description
async	CLEAR_EVENT_THROTTLE	Clear event throttling

4.2. Telemetry

Name	Type	Description
NumSuccessfulAllocations	U32	The number of successful buffer allocations
NumFailedAllocations	U32	The number of failed buffer allocations
NumDataProds	U32	Number of data products handled
NumBytes	U32	Number of bytes handled

4.3. Events

Name	Severity	Description
BufferAllocationFailed	warning high	Buffer allocation failed

5. Example Uses

5.1. Topology Diagrams

The following topology diagrams show how to connect Svc::DpManager to a client component, a buffer manager, and a data product writer. The diagrams use the following instances:

• bufferManager: An instance of Svc::BufferManager.

• dpManager: An instance of Svc::DpManager.

• dpWriter: An instance of Svc::DpWriter.

• producer: A client component that produces data products. productRequestOut is the special product request port. productRecvIn is the special product recv port.

The connections shown use port zero for requesting, receiving, and sending data product buffers. If DpManagerNumPorts is greater than one, then you can also use other ports, e.g., port one or port two. That way you can use one DpManager instance to support multiple sets of connections.

5.1.1. Synchronously Getting Data Product Buffers

5.1.2. Asynchronously Requesting Data Product Buffers

5.1.3. Sending Data Products

5.2. Sequence Diagrams

5.2.1. Synchronously Getting a Data Product Buffer

sequenceDiagram
    activate producer
    producer->>dpManager: Request buffer [productGetIn]
    dpManager->>bufferManager: Request buffer B [bufferGetOut]
    bufferManager-->>dpManager: Return B
    dpManager->>dpManager: Store B into producer
    dpManager-->>producer: Return SUCCESS
    deactivate producer

5.2.2. Asynchronously Requesting a Data Product Buffer

sequenceDiagram
    activate producer
    activate dpManager
    producer-)dpManager: Request buffer [productRequestIn]
    dpManager->>bufferManager: Request buffer B [bufferGetOut]
    bufferManager-->>dpManager: Return B
    dpManager-)producer: Send B [productResponseOut]
    deactivate dpManager
    deactivate producer

5.2.3. Sending a Data Product

sequenceDiagram
    activate producer
    activate dpManager
    activate dpWriter
    producer-)dpManager: Send buffer B [productSendIn]
    dpManager-)dpWriter: Send B [productSendOut]
    dpWriter->>bufferManager: Deallocate B
    bufferManager-->>dpWriter: Return
    deactivate dpWriter
    deactivate dpManager
    deactivate producer