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> For a complete documentation index, see https://docs.nvidia.com/nemo/automodel/llms.txt.
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# nemo_automodel.components.moe.uccl_ep.buffer

UCCLBuffer: a DeepEP-compatible Buffer backed by UCCL-EP.

This module re-exports the canonical Buffer implementation under the UCCLBuffer
alias expected by nemo\_automodel, with automatic intranode detection.

## Module Contents

### Classes

| Name                                                                       | Description                                       |
| -------------------------------------------------------------------------- | ------------------------------------------------- |
| [`EventHandle`](#nemo_automodel-components-moe-uccl_ep-buffer-EventHandle) | -                                                 |
| [`UCCLBuffer`](#nemo_automodel-components-moe-uccl_ep-buffer-UCCLBuffer)   | Buffer subclass that auto-detects intranode mode. |

### Data

[`__all__`](#nemo_automodel-components-moe-uccl_ep-buffer-__all__)

### API

```python
class nemo_automodel.components.moe.uccl_ep.buffer.EventHandle()
```

```python
class nemo_automodel.components.moe.uccl_ep.buffer.UCCLBuffer(
    group,
    num_nvl_bytes: int = 0,
    num_rdma_bytes: int = 0,
    low_latency_mode: bool = False,
    num_qps_per_rank: int = 24,
    allow_nvlink_for_low_latency_mode: bool = True,
    allow_mnnvl: bool = False,
    explicitly_destroy: bool = False,
    is_intranode: bool = False
)
```

**Bases:** [Buffer](/nemo-automodel/nemo_automodel/components/moe/uccl_ep/_buffer#nemo_automodel-components-moe-uccl_ep-_buffer-Buffer)

Buffer subclass that auto-detects intranode mode.

When all EP ranks fit on a single node (group\_size \<= LOCAL\_WORLD\_SIZE),
RDMA is disabled and only NVLink is used, avoiding RDMA MR registration
failures on single-node setups.

```python
nemo_automodel.components.moe.uccl_ep.buffer.__all__ = ['UCCLBuffer', 'Buffer', 'EventOverlap', 'EventHandle']
```