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# holoscan::DFFTCollector

> DFFTCollector class (Data Frame Flow Tracking - DFFT) collects the metrics data at the end of the execution of the leaf operators.

`DFFTCollector` class (Data Frame Flow Tracking - DFFT) collects the metrics data at the end of the execution of the leaf operators.

It updates the [DataFlowTracker](dataflowtracker) objects with the final result after every execution of a leaf operator. It also updates the receive timestamp of the root operators to the tick start time of the operators.

```cpp showLineNumbers={false}
#include <holoscan/dfft_collector.hpp>
```

**Inherits from:** `nvidia::gxf::Monitor` (public)

---

## Methods

### on\_execute\_abi \[#onexecuteabi]

```cpp showLineNumbers={false}
gxf_result_t holoscan::DFFTCollector::on_execute_abi(
    gxf_uid_t eid,
    uint64_t timestamp,
    gxf_result_t code
) override
```

Called after the execution of an entity.

Whenever a Holoscan operator's entity or any other Entity (e.g., entity containing the Broadcast extension component) is finished executing, this function is called.

**Parameters**

**`eid`** `gxf_uid_t`

GXF entity id of the entity that has finished executing.

---

**`timestamp`** `uint64_t`

Timestamp of the execution.

---

**`code`** `gxf_result_t`

Result code of the execution.

---

### data\_flow\_tracker \[#dataflowtracker]

```cpp showLineNumbers={false}
void holoscan::DFFTCollector::data_flow_tracker(
    holoscan::DataFlowTracker *d
)
```

Set the [DataFlowTracker](dataflowtracker) object for this `DFFTCollector` object.

**Parameters**

**`d`** `holoscan::DataFlowTracker *`

The dataflow tracker object to be set.

---

---

## Member variables

| Name                          | Type                             | Description                                                                                                                                                                                       |
| ----------------------------- | -------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `data_flow_tracker_`          | `holoscan::DataFlowTracker *`    | Pointer to the [DataFlowTracker](dataflowtracker) object to update the [DataFlowTracker](dataflowtracker) object with the final results at the end of the execution of a tick of a leaf operator. |
| `leaf_last_execution_count_`  | `std::map< gxf_uid_t, int64_t >` | A map of codelet id and the last execution count number from the nvidia::gxf::Codelet.                                                                                                            |
| `probe_last_execution_count_` | `std::map< gxf_uid_t, int64_t >` | A map of codelet id and the last execution count number from the nvidia::gxf::Codelet.                                                                                                            |