[Lora]Load tuned multi-lora kernel configs from json files (#26319)

Signed-off-by: li2haipeng <44383182+li2haipeng@users.noreply.github.com>
Signed-off-by: Haipeng Li <li2haipeng@gmail.com>
Co-authored-by: Jee Jee Li <pandaleefree@gmail.com>

Author: li2haipeng

vllm/lora/ops/triton_ops/README_TUNING.md

@@ -0,0 +1,51 @@
+# Multi-LoRA Tuning
+
+**Note**: The LoRA configuration folder should be specified by exporting `VLLM_TUNED_CONFIG_FOLDER=/path/to/configs`. Without this, the shrink/expand kernels will use default configurations.
+
+## Tuning Process
+
+Multi-lora shrink/expand Triton kernel tuning follows a similar methodology from [Triton MoE tuning](https://github.com/vllm-project/vllm/blob/main/benchmarks/kernels/benchmark_moe.py).
+
+**Step 1**
+Define the searching space. An example searching space:
+
+```python
+block_m_range = [16, 32, 64, 128, 256]
+block_n_range = [32, 64, 128, 256]
+block_k_range = [32, 64, 128, 256]
+num_warps_range = [4, 8]
+num_stage_range = [2, 3, 4, 5]
+num_ctas_range = [1]
+split_k_range = [4, 8, 16, 32, 64]
+```
+
+**Step 2**
+Get all hidden_state sizes and num_slices that the target model uses for a specific TP size.
+
+For example, we can aquire those info by simply checking [add_lora_linear](https://github.com/li2haipeng/vllm/blob/multi_lora_v01011/vllm/lora/punica_wrapper/punica_gpu.py#L192):
+
+```python
+print(f"x_shape: {x.view(-1, x.shape[-1]).shape}")
+print(f"num_sclises: {len(output_slices)}")
+for i in range(len(output_slices)):
+    print(f"a{i} shape: {lora_a_stacked[i].shape}")
+    print(f"b{i} shape: {lora_b_stacked[i].shape}")
+print("y_shape", y.shape)
+```
+
+**Step 3**
+Benchmark the shrink/expand kernel runtime with different kernel configurations generated from the pre-defined search space by performing a grid search to find the optimal kernel configuration. vLLM's [benchmark_lora.py](https://github.com/vllm-project/vllm/blob/main/benchmarks/kernels/benchmark_lora.py) can be used to search for configurations for different shapes.
+
+## Config Files
+
+### File Name
+
+For `shrink`, the config file is named as `{gpu_name}_SHRINK.json`, e.g. `NVIDIA_H200_SHRINK.json`.
+
+For `expand`, the config fileis named as `{gpu_name}_EXPAND_{add_input}.json`, e.g. `NVIDIA_H200_EXPAND_TRUE.json`.
+
+The `gpu_name` can be automatically detected by calling `torch.cuda.get_device_name()`
+
+### Json Structure
+
+Optimal kernel configuration files are saved as JSON files with the structure `config_data[max_loras][num_slices][m][k][n]`

vllm/lora/ops/triton_ops/lora_expand_op.py

@@ -10,7 +10,7 @@
 import torch
 
 from vllm.lora.ops.triton_ops.kernel_utils import do_expand_kernel
-from vllm.lora.ops.triton_ops.utils import _get_lora_b_ptr
+from vllm.lora.ops.triton_ops.utils import _get_lora_b_ptr, get_lora_op_configs
 from vllm.triton_utils import tl, triton
 from vllm.utils import direct_register_custom_op
 
@@ -201,12 +201,21 @@ def _lora_expand(
     NUM_SLICES = len(lora_b_weights)
 
     # Triton kernel configs.
-    BLOCK_M = 64
-    BLOCK_N = 128
-    BLOCK_K = 16
-    NUM_WARPS = 4
-    NUM_CTAS = 1
-    NUM_STAGES = 2
+    kernel_config = get_lora_op_configs(
+        op_type="expand",
+        max_loras=MAX_LORAS,
+        batch=M,
+        hidden_size=MAX_N,
+        rank=K,
+        num_slices=NUM_SLICES,
+        add_inputs=add_inputs,
+    )
+    BLOCK_M = kernel_config["block_m"]
+    BLOCK_N = kernel_config["block_n"]
+    BLOCK_K = kernel_config["block_k"]
+    NUM_WARPS = kernel_config["num_warps"]
+    NUM_CTAS = kernel_config["num_ctas"]
+    NUM_STAGES = kernel_config["num_stages"]
 
     EVEN_K = K % BLOCK_K == 0  # type: ignore
 

vllm/lora/ops/triton_ops/lora_shrink_op.py

@@ -10,7 +10,7 @@
 import torch
 
 from vllm.lora.ops.triton_ops.kernel_utils import do_shrink_kernel
-from vllm.lora.ops.triton_ops.utils import _get_lora_a_ptr
+from vllm.lora.ops.triton_ops.utils import _get_lora_a_ptr, get_lora_op_configs
 from vllm.triton_utils import tl, triton
 from vllm.utils import direct_register_custom_op
 
@@ -177,14 +177,21 @@ def _lora_shrink(
     MAX_LORAS = lora_ids.size(0)
 
     # Triton kernel configs
-    BLOCK_M = 32
-    BLOCK_N = 16
-    BLOCK_K = 256 if M < 128 else 32
-    SPLIT_K = 64 if M < 128 else 8
-    NUM_WARPS = 4
-    NUM_CTAS = 1
-    NUM_STAGES = 2
-
+    kernel_config = get_lora_op_configs(
+        "shrink",
+        max_loras=MAX_LORAS,
+        batch=M,
+        hidden_size=K,
+        rank=N,
+        num_slices=NUM_SLICES,
+    )
+    BLOCK_M = kernel_config["block_m"]
+    BLOCK_N = kernel_config["block_n"]
+    BLOCK_K = kernel_config["block_k"]
+    SPLIT_K = kernel_config["split_k"]
+    NUM_WARPS = kernel_config["num_warps"]
+    NUM_STAGES = kernel_config["num_stages"]
+    NUM_CTAS = kernel_config["num_ctas"]
     EVEN_K = K % (BLOCK_K * SPLIT_K) == 0  # type: ignore
 
     # TODO (varun): This grid formulation maximizes parallelization at the

vllm/lora/ops/triton_ops/utils.py

@@ -1,8 +1,18 @@
 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 
+import functools
+import json
+from pathlib import Path
+from typing import Any
+
 import torch
 
+from vllm import envs
+from vllm.logger import init_logger
+
+logger = init_logger(__name__)
+
 _LORA_A_PTR_DICT: dict[tuple[int, ...], tuple[torch.tensor, ...]] = {}
 _LORA_B_PTR_DICT: dict[tuple[int, ...], tuple[torch.tensor, ...]] = {}
 
@@ -133,3 +143,108 @@ def _get_lora_b_ptr(
         MAX_N,
     )
     return _LORA_B_PTR_DICT.get(key)
+
+
+@functools.lru_cache
+def load_lora_op_config(op_type: str, add_inputs: bool | None) -> dict | None:
+    user_defined_config_folder = envs.VLLM_TUNED_CONFIG_FOLDER
+    if user_defined_config_folder is not None:
+        gpu_name = torch.cuda.get_device_name()
+        gpu_name = gpu_name.replace(" ", "_")
+        gpu_name = gpu_name.replace("-", "_")
+
+        config_fname = None
+        if op_type == "shrink":
+            config_fname = f"{gpu_name}_{op_type.upper()}.json"
+        else:
+            assert op_type == "expand"
+            config_fname = (
+                f"{gpu_name}_{op_type.upper()}_{str(add_inputs).upper()}.json"
+            )
+
+        config_path = Path(f"{user_defined_config_folder}/{config_fname}")
+        if not config_path.exists():
+            logger.warning_once(f"No LoRA kernel configs founded in {config_path}")
+            return None
+
+        # Load json
+        logger.info_once(f"Using tuned LoRA kernel configs from {config_path}.")
+        with open(str(config_path)) as f:
+            config_data = json.load(f)
+    else:
+        config_data = None
+
+    return config_data
+
+
+@functools.lru_cache
+def get_lora_op_configs(
+    op_type: str,
+    max_loras: int,
+    batch: int,
+    hidden_size: int,
+    rank: int,
+    num_slices: int,
+    add_inputs: bool | None = None,
+) -> dict[str, int | None]:
+    assert op_type in ["shrink", "expand"]
+
+    # default config
+    default = {}
+    if op_type == "shrink":
+        default = {
+            "block_m": 32,
+            "block_n": 16,
+            "block_k": 256 if batch < 128 else 32,
+            "split_k": 64 if batch < 128 else 8,
+            "num_warps": 4,
+            "num_ctas": 1,
+            "num_stages": 2,
+            "max_nreg": None,
+        }
+    else:
+        default = {
+            "block_m": 64,
+            "block_n": 128,
+            "block_k": 16,
+            "num_warps": 4,
+            "num_ctas": 1,
+            "num_stages": 2,
+            "max_nreg": None,
+        }
+    m = batch
+
+    k, n = (hidden_size, rank) if op_type == "shrink" else (rank, hidden_size)
+
+    config_data: Any
+    config_data = load_lora_op_config(op_type, add_inputs)
+    if not config_data:
+        logger.warning_once("Using default LoRA kernel configs")
+        return default
+
+    # config is structured as config_data[max_loras][num_slices][m][k][n] = {}
+    # slice by max_loras
+    config_data = (
+        config_data.get(str(max_loras))
+        or config_data[min(config_data.keys(), key=lambda x: abs(int(x) - max_loras))]
+    )
+    # slice by num_slices
+    config_data = config_data[str(num_slices)]
+    # slice by m
+    config_data = (
+        config_data.get(str(m))
+        or config_data[min(config_data.keys(), key=lambda x: abs(int(x) - m))]
+    )
+    # slice by k
+    config_data = (
+        config_data.get(str(k))
+        or config_data[min(config_data.keys(), key=lambda x: abs(int(x) - k))]
+    )
+    # slice by n
+    config_data = (
+        config_data.get(str(n))
+        or config_data[min(config_data.keys(), key=lambda x: abs(int(x) - n))]
+    )
+
+    assert config_data is not None
+    return config_data