megatron lm custom flow (#152)

This PR introduces a new custom workflow for generating performance reports for Megatron LM, utilizing trace data and custom performance model adjustments.

Introduces a new script for consolidating trace data and outputting Excel reports.
Updates performance model mappings to include FusedAttnFunc for SDPA operations.

Author: ajassani

examples/custom_workflows/generate_perf_report_megatron_lm.py

@@ -0,0 +1,105 @@
+import argparse
+import json
+import pandas as pd
+from TraceLens import TraceToTree
+from TraceLens import TreePerfAnalyzer
+from TraceLens.PerfModel import dict_cat2names
+
+from TraceLens.PerfModel import SDPA
+class transformer_engine_attention(SDPA):
+    """
+    Context: The FusedAttnFunc is a pytorch extention for the attention kernel.
+    Unfortunately, the args does not have a bool flag for is_causal.
+    Instead, it has a str arg which is not recorded in the trace.
+
+    Solution: Based on the LLM use case we make the assumption that
+    the attention is always causal.
+    Since this might not be the case for other use cases, 
+    we dont add this natively to the perf model and instead add it here 
+    """
+    @staticmethod
+    def get_param_details(event):
+    # ref TransformerEngine/transformer_engine/pytorch/cpp_extensions/fused_attn.py
+    # https://github.com/NVIDIA/TransformerEngine/blob/51cd441501e8e6dee18c00056f008e1b53b89ebd/transformer_engine/pytorch/attention/dot_product_attention/backends.py#L881
+        input_dims = event['args']['Input Dims']
+        q_idx = None
+        for i, dim in enumerate(input_dims):
+            if len(dim)==4:
+                q_idx = i
+                break
+        assert q_idx is not None, "query index not found"
+        q_shape, k_shape, v_shape = input_dims[q_idx: q_idx+3]
+        B, N_Q, H_Q, d_h = q_shape
+        assert k_shape == v_shape, f"Key and value shapes are different: {k_shape} != {v_shape}"
+        _, N_KV, H_KV, _ = k_shape 
+        is_causal = True
+        dropout_p = 0.0
+        return {"B": B, "N_Q": N_Q, "H_Q": H_Q, "N_KV": N_KV, "H_KV": H_KV, "d_h": d_h,
+                "dropout": dropout_p, "causal": is_causal, "flash_impl": False}    
+
+def main():
+    parser = argparse.ArgumentParser(description='Process a JSON trace profile and generate performance report tables.')
+    parser.add_argument('--profile_json_path', type=str, required=True, help='Path to the profile.json file')
+    parser.add_argument('--output_xlsx_path', type=str, required=True, help='Path to the output Excel file')
+    parser.add_argument('--gpu_arch_json_path', type=str, default=None, help='Path to the GPU architecture JSON file')
+    args = parser.parse_args()
+
+    # Load the arch json
+    gpu_arch_json = None
+    if args.gpu_arch_json_path:
+        with open(args.gpu_arch_json_path, 'r') as f:
+            gpu_arch_json = json.load(f)
+    perf_analyzer = TreePerfAnalyzer.from_file(profile_filepath=args.profile_json_path, arch=gpu_arch_json)
+
+    agg_metrics = ['mean', 'median', 'std', 'min', 'max']
+
+    # Generate base DataFrames
+    df_gpu_timeline = perf_analyzer.get_df_gpu_timeline()
+    df_kernel_launchers = perf_analyzer.get_df_kernel_launchers()
+    df_kernel_launchers_summary = perf_analyzer.get_df_kernel_launchers_summary(df_kernel_launchers)
+    df_kernel_launchers_unique_args = perf_analyzer.get_df_kernel_launchers_unique_args(df_kernel_launchers, 
+                                                                                        agg_metrics=agg_metrics, 
+                                                                                        include_pct=True)
+
+    # Dictionary to hold the op-specific DataFrames
+    op_dfs = {}
+
+    # update the dict_cat2names to include FusedAttnFunc
+    dict_cat2names['SDPA'].append('FusedAttnFunc')
+    dict_name_to_custom_perf_model = {'FusedAttnFunc': transformer_engine_attention}
+
+    for op_cat, op_names in dict_cat2names.items():
+        # Filter events belonging to the current category
+        op_events = [event for event in perf_analyzer.tree.events if event['name'] in op_names]
+
+        if op_cat in ['GEMM', 'UnaryElementwise', 'BinaryElementwise']:
+            # For GEMM: create a single table that covers both fwd and bwd.
+            df_ops = perf_analyzer.build_df_perf_metrics(op_events, bwd=False, include_kernel_names=True, include_args=True,
+                                                        dict_name_to_perf_model=dict_name_to_custom_perf_model)
+            df_ops = perf_analyzer.summarize_df_perf_metrics(df_ops, agg_metrics)
+            op_dfs[op_cat] = df_ops
+        else:
+            # For FLASH_ATTN and CONV: create separate tables for forward and backward passes.
+            df_ops_fwd = perf_analyzer.build_df_perf_metrics(op_events, bwd=False, include_kernel_names=True, include_args=True,
+                                                            dict_name_to_perf_model=dict_name_to_custom_perf_model)
+            df_ops_fwd = perf_analyzer.summarize_df_perf_metrics(df_ops_fwd, agg_metrics)
+            df_ops_bwd = perf_analyzer.build_df_perf_metrics(op_events, bwd=True, include_kernel_names=True, include_args=True,
+                                                            dict_name_to_perf_model=dict_name_to_custom_perf_model)
+            df_ops_bwd = perf_analyzer.summarize_df_perf_metrics(df_ops_bwd, agg_metrics)
+            op_dfs[f"{op_cat}_fwd"] = df_ops_fwd
+            op_dfs[f"{op_cat}_bwd"] = df_ops_bwd
+
+    # Write all DataFrames to separate sheets in an Excel workbook
+    with pd.ExcelWriter(args.output_xlsx_path) as writer:
+        df_gpu_timeline.to_excel(writer, sheet_name='gpu_timeline', index=False)
+        df_kernel_launchers_summary.to_excel(writer, sheet_name='kernel_launchers_summary', index=False)
+        df_kernel_launchers_unique_args.to_excel(writer, sheet_name='kernel_launchers_unique_args', index=False)
+        
+        # Write each op category DataFrame
+        for sheet_name, df in op_dfs.items():
+            df.to_excel(writer, sheet_name=sheet_name, index=False)
+
+    print(f"DataFrames successfully written to {args.output_xlsx_path}")
+
+if __name__ == "__main__":
+    main()