latency test enhancement - part 1 (#909)

python/pyproject.toml

@@ -21,7 +21,7 @@ dependencies = [
 
 [project.optional-dependencies]
 srt = ["aiohttp", "fastapi", "hf_transfer", "huggingface_hub", "interegular", "packaging", "pillow",
-       "psutil", "pydantic", "torch", "uvicorn", "uvloop", "zmq", "vllm==0.5.3.post1", "outlines>=0.0.44", "python-multipart"]
+       "psutil", "pydantic", "torch", "uvicorn", "uvloop", "zmq", "vllm==0.5.3.post1", "outlines>=0.0.44", "python-multipart", "jsonlines"]
 openai = ["openai>=1.0", "tiktoken"]
 anthropic = ["anthropic>=0.20.0"]
 litellm = ["litellm>=1.0.0"]

python/sglang/bench_latency.py

 """
 Benchmark the latency of a given model. It accepts arguments similar to those of launch_server.py.
 
-# Usage (latency test):
+# Usage (latency test) with dummy weights:
 python -m sglang.bench_latency --model-path meta-llama/Meta-Llama-3-8B-Instruct --load-format dummy
 
 # Usage (correctness test):
 python -m sglang.bench_latency --model-path TinyLlama/TinyLlama-1.1B-Chat-v0.4 --correct
 
-### Reference output:
+### Reference output (of the correctness test above, can be gpu dependent):
 prefill logits (first half) tensor([[-10.0312,  -9.5000,   0.8936,  ...,  -4.9414,  -3.2402,  -3.3633],
         [-10.0312,  -9.5000,   0.8936,  ...,  -4.9414,  -3.2402,  -3.3633],
         [ -9.1875, -10.2500,   2.7109,  ...,  -4.3359,  -4.0664,  -4.1328]],
@@ -31,7 +31,9 @@ import dataclasses
 import logging
 import multiprocessing
 import time
+from typing import Tuple
 
+import jsonlines
 import numpy as np
 import torch
 import torch.distributed as dist
@@ -47,25 +49,34 @@ from sglang.srt.utils import suppress_other_loggers
 
 @dataclasses.dataclass
 class BenchArgs:
-    batch_size: int = 1
+    batch_size: Tuple[int] = (1,)
     input_len: int = 1024
     output_len: int = 4
+    result_filename: str = ""
     correctness_test: bool = False
     # This is only used for correctness test
     cut_len: int = 4
 
     @staticmethod
     def add_cli_args(parser: argparse.ArgumentParser):
-        parser.add_argument("--batch-size", type=int, default=BenchArgs.batch_size)
+        parser.add_argument(
+            "--batch-size", type=int, nargs="+", default=BenchArgs.batch_size
+        )
         parser.add_argument("--input-len", type=int, default=BenchArgs.input_len)
         parser.add_argument("--output-len", type=int, default=BenchArgs.output_len)
+        parser.add_argument(
+            "--result-filename", type=str, default=BenchArgs.result_filename
+        )
         parser.add_argument("--correctness-test", action="store_true")
         parser.add_argument("--cut-len", type=int, default=BenchArgs.cut_len)
 
     @classmethod
     def from_cli_args(cls, args: argparse.Namespace):
-        attrs = [attr.name for attr in dataclasses.fields(cls)]
-        return cls(**{attr: getattr(args, attr) for attr in attrs})
+        # use the default value's type to case the args into correct types.
+        attrs = [(attr.name, type(attr.default)) for attr in dataclasses.fields(cls)]
+        return cls(
+            **{attr: attr_type(getattr(args, attr)) for attr, attr_type in attrs}
+        )
 
 
 def load_model(server_args, tp_rank):
@@ -93,7 +104,7 @@ def load_model(server_args, tp_rank):
     return model_runner, tokenizer
 
 
-def prepare_inputs(bench_args, tokenizer):
+def prepare_inputs_for_correctness_test(bench_args, tokenizer):
     prompts = [
         "The capital of France is",
         "The capital of the United Kindom is",
@@ -119,7 +130,9 @@ def prepare_inputs(bench_args, tokenizer):
     return input_ids, reqs
 
 
-def prepare_extend_inputs(bench_args, input_ids, reqs, model_runner):
+def prepare_extend_inputs_for_correctness_test(
+    bench_args, input_ids, reqs, model_runner
+):
     for i in range(len(reqs)):
         req = reqs[i]
         req.input_ids += input_ids[i][bench_args.cut_len :]
@@ -129,8 +142,8 @@ def prepare_extend_inputs(bench_args, input_ids, reqs, model_runner):
     return reqs
 
 
-def prepare_synthetic_inputs(bench_args, tokenizer):
-    input_ids = np.ones((bench_args.batch_size, bench_args.input_len), dtype=np.int32)
+def prepare_synthetic_inputs_for_latency_test(batch_size, input_len):
+    input_ids = np.ones((batch_size, input_len), dtype=np.int32)
     sampling_params = SamplingParams(
         temperature=0,
         max_new_tokens=BenchArgs.output_len,
@@ -179,7 +192,7 @@ def correctness_test(
     model_runner, tokenizer = load_model(server_args, tp_rank)
 
     # Prepare inputs
-    input_ids, reqs = prepare_inputs(bench_args, tokenizer)
+    input_ids, reqs = prepare_inputs_for_correctness_test(bench_args, tokenizer)
 
     if bench_args.cut_len > 0:
         # Prefill
@@ -187,7 +200,9 @@ def correctness_test(
         rank_print("prefill logits (first half)", next_token_logits)
 
     # Prepare extend inputs
-    reqs = prepare_extend_inputs(bench_args, input_ids, reqs, model_runner)
+    reqs = prepare_extend_inputs_for_correctness_test(
+        bench_args, input_ids, reqs, model_runner
+    )
 
     # Extend
     next_token_ids, next_token_logits, batch = extend(reqs, model_runner)
@@ -218,8 +233,13 @@ def latency_test(
         f"max_batch_size={model_runner.max_total_num_tokens // (bench_args.input_len + bench_args.output_len)}"
     )
 
+    # To make this PR easier to review, for now, only do the first element in batch_size tuple.
+    bench_args.batch_size = bench_args.batch_size[0]
+
     # Prepare inputs
-    reqs = prepare_synthetic_inputs(bench_args, tokenizer)
+    reqs = prepare_synthetic_inputs_for_latency_test(
+        bench_args.batch_size, bench_args.input_len
+    )
 
     def clear():
         model_runner.req_to_token_pool.clear()
@@ -227,6 +247,11 @@ def latency_test(
 
     @torch.inference_mode()
     def run_once(output_len):
+        measurement_results = {
+            "batch_size": bench_args.batch_size,
+            "output_len": output_len,
+        }
+
         # Prefill
         torch.cuda.synchronize()
         tot_latency = 0
@@ -239,6 +264,8 @@ def latency_test(
         rank_print(
             f"Prefill. latency: {prefill_latency:6.5f} s, throughput: {throughput:9.2f} token/s"
         )
+        measurement_results["prefill_latency"] = prefill_latency
+        measurement_results["prefill_throughput"] = throughput
 
         # Decode
         for i in range(output_len):
@@ -258,6 +285,8 @@ def latency_test(
         rank_print(
             f"Decode.  avg latency: {avg_decode_latency:6.5f} s, avg throughput: {avg_decode_throughput:9.2f} token/s"
         )
+        measurement_results["avg_decode_latency"] = avg_decode_latency
+        measurement_results["avg_decode_throughput"] = avg_decode_throughput
 
         throughput = (
             (bench_args.input_len + bench_args.output_len)
@@ -267,13 +296,22 @@ def latency_test(
         rank_print(
             f"Total. latency: {tot_latency:6.3f} s, throughput: {throughput:9.2f} token/s"
         )
+        measurement_results["total_latency"] = tot_latency
+        measurement_results["total_throughput"] = throughput
+        return measurement_results
 
     # Warm up
     run_once(4)
     clear()
 
     # Run again
-    run_once(bench_args.output_len)
+    result_list = []
+    result_list.append(run_once(bench_args.output_len))
+
+    # Write results in jsonlines format.
+    if bench_args.result_filename:
+        with jsonlines.open(bench_args.result_filename, "a") as f:
+            f.write_all(result_list)
 
 
 def main(server_args, bench_args):