disable all_to_all_fp8 in intranode

colossalai/quantization/fp8.py

@@ -1,3 +1,4 @@
+import os
 from typing import Any, Optional, Tuple
 
 import numpy as np
@@ -23,6 +24,24 @@ def wait(self):
             self.remain_ops()
 
 
+def process_group_is_intranode(pg):
+    if pg is None:
+        from torch.distributed.distributed_c10d import _get_default_group
+
+        pg = _get_default_group()
+
+    local_world_size = None
+    for var in ["LOCAL_WORLD_SIZE", "OMPI_COMM_WORLD_LOCAL_SIZE", "SLURM_TASKS_PER_NODE"]:
+        if var in os.environ:
+            local_world_size = int(os.environ["LOCAL_WORLD_SIZE"])
+    if local_world_size is None:
+        local_world_size = torch.cuda.device_count()
+
+    group_ranks = dist.get_process_group_ranks(pg)
+    group_ranks_node_ids = [rank // local_world_size for rank in group_ranks]
+    return min(group_ranks_node_ids) == max(group_ranks_node_ids)
+
+
 def cast_to_fp8(
     inp: torch.Tensor, fp8_format="e4m3", per_channel_scale=False, out=None
 ) -> Tuple[torch.Tensor, torch.Tensor]:
@@ -92,7 +111,7 @@ def cast_from_fp8(
     return ret.to(ret_type)
 
 
-def all_reduce_fp8(
+def _all_reduce_fp8(
     tensor: torch.Tensor, fp8_format="e4m3", op=ReduceOp.SUM, group=None, async_op: bool = False
 ) -> Optional[Handle]:
     r"""
@@ -159,7 +178,15 @@ def cat_op():
         cat_op()
 
 
-def all_to_all_single_fp8(
+def all_reduce_fp8(
+    tensor: torch.Tensor, fp8_format="e4m3", op=ReduceOp.SUM, group=None, async_op: bool = False
+) -> Optional[Handle]:
+    # fall back to default op due to performance issue
+    return dist.all_reduce(tensor, op=op, group=group, async_op=async_op)
+
+
+@torch.compile(mode="max-autotune-no-cudagraphs", dynamic=False)
+def _all_to_all_single_fp8(
     output, input, output_split_sizes=None, input_split_sizes=None, fp8_format="e5m2", group=None, async_op=False
 ) -> Optional[Handle]:
     r"""
@@ -222,6 +249,33 @@ def cast_op():
         cast_op()
 
 
+def all_to_all_single_fp8(
+    output, input, output_split_sizes=None, input_split_sizes=None, fp8_format="e5m2", group=None, async_op=False
+) -> Optional[Handle]:
+    r"""
+    This is wrapper for _all_to_all_single_fp8.
+    """
+    if process_group_is_intranode(group):
+        return dist.all_to_all_single(
+            output,
+            input,
+            output_split_sizes=output_split_sizes,
+            input_split_sizes=input_split_sizes,
+            group=group,
+            async_op=async_op,
+        )
+    else:
+        return _all_to_all_single_fp8(
+            output,
+            input,
+            fp8_format=fp8_format,
+            output_split_sizes=output_split_sizes,
+            input_split_sizes=input_split_sizes,
+            group=group,
+            async_op=async_op,
+        )
+
+
 def cast_to_fp8_pipeline(inp: Any) -> None:
     """
     Cast the hidden_states tensor of inp object to fp8 format before p2p communication in pipeline.
@@ -293,7 +347,7 @@ def cast_from_fp8_pipeline(inp: Any, del_metadata=True) -> None:
         del inp["dtype"]
 
 
-def reduce_scatter_fp8(
+def _reduce_scatter_fp8(
     output: torch.Tensor, input_list, group, fp8_format="e5m2", async_op: bool = False
 ) -> Optional[Handle]:
     r"""
@@ -338,6 +392,13 @@ def cast_op():
         cast_op()
 
 
+def reduce_scatter_fp8(
+    output: torch.Tensor, input_list, group, fp8_format="e5m2", async_op: bool = False
+) -> Optional[Handle]:
+    # fall back to default op due to performance issue
+    return dist.reduce_scatter(output, input_list, group=group, async_op=async_op)
+
+
 def fp8_compress_ddp_grad_comm_hook_async(
     process_group: dist.ProcessGroup,
     bucket: dist.GradBucket,
@@ -617,10 +678,9 @@ def cast_op():
         cast_op()
 
 
-def all_to_all_fp8(output_list, input_list, group=None, fp8_format="e5m2", async_op=False):
-
+@torch.compile(mode="max-autotune-no-cudagraphs", dynamic=False)
+def _all_to_all_fp8(output_list, input_list, group=None, fp8_format="e5m2", async_op=False):
     world_size = dist.get_world_size(group)
-
     input_type = input_list[0].dtype
     fp8_type = torch.float8_e4m3fn if fp8_format == "e4m3" else torch.float8_e5m2
     scale_list = []
@@ -651,6 +711,13 @@ def cast_op():
         cast_op()
 
 
+def all_to_all_fp8(output_list, input_list, group=None, fp8_format="e5m2", async_op=False):
+    if process_group_is_intranode(group):
+        return dist.all_to_all(output_list, input_list, group=group, async_op=async_op)
+    else:
+        return _all_to_all_fp8(output_list, input_list, group=group, fp8_format=fp8_format, async_op=async_op)
+
+
 def gather_fp8(output_list, input_, group=None, fp8_format="e5m2", async_op: bool = False) -> Optional[Handle]:
 
     world_size = dist.get_world_size(group)