[KV Connector] Support using FlexKV as KV Cache Offloading option. (#34328)
Signed-off-by: phaedonsun <phaedonsun@tencent.com> Co-authored-by: phaedonsun <phaedonsun@tencent.com>
This commit is contained in:
@@ -44,6 +44,12 @@ For NixlConnector, you may also specify one or multiple NIXL_Backend. Such as:
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--kv-transfer-config '{"kv_connector":"OffloadingConnector","kv_role":"kv_both","kv_connector_extra_config":{"block_size": 64, "cpu_bytes_to_use": 1000000000}}'
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```
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- **FlexKVConnectorV1**: refer to [examples/offline_inference/prefix_caching_flexkv.py](../../examples/offline_inference/prefix_caching_flexkv.py) for the example usage of FlexKVConnectorV1. FlexKV is a distributed KV Store and multi-level cache management system for ultra-large-scale LLM inference.
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```bash
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--kv-transfer-config '{"kv_connector":"FlexKVConnectorV1","kv_role":"kv_both"}'
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```
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## Benchmarks
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Please refer to [benchmarks/disagg_benchmarks](../../benchmarks/disagg_benchmarks) for disaggregated prefilling benchmarks.
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221
examples/offline_inference/prefix_caching_flexkv.py
Normal file
221
examples/offline_inference/prefix_caching_flexkv.py
Normal file
@@ -0,0 +1,221 @@
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# SPDX-License-Identifier: Apache-2.0
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# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
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"""
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This example shows how to use FlexKV with vLLM for prefix caching.
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FlexKV is a distributed KV Store and multi-level cache management system for
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ultra-large-scale LLM inference.
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Requirements:
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- Install FlexKV (https://github.com/taco-project/FlexKV):
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1. git clone git@github.com:taco-project/FlexKV.git
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2. cd FlexKV && bash build.sh
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- Ensure FlexKV is compatible with your vLLM version.
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Usage:
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1. Run this script:
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python examples/offline_inference/prefix_caching_flexkv.py \
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--model /path/to/your/model
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2. Arguments:
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--model Path or name of the model (required)
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--tp-size Tensor parallel size (default: 1)
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--gpu-memory-util GPU memory utilization (default: 0.4)
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3. The script will:
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- Create a FlexKV configuration file.
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- Set the FLEXKV_CONFIG_PATH environment variable.
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- Run vLLM with FlexKVConnectorV1 enabled.
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- Compare results between regular execution, vLLM's default prefix
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caching, and FlexKV.
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"""
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import argparse
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import json
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import os
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import time
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from vllm import LLM, SamplingParams
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from vllm.distributed import cleanup_dist_env_and_memory
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# NOTE: This is just a running example. For benchmarking purpose,
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# please see benchmarks/benchmark_prefix_caching.py
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def parse_args():
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parser = argparse.ArgumentParser(
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description="Example of using FlexKV with vLLM for prefix caching."
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)
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parser.add_argument(
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"--model",
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type=str,
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required=True,
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help="Path or name of the model to use.",
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)
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parser.add_argument(
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"--tp-size",
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type=int,
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default=1,
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help="Tensor parallel size (default: 1).",
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)
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parser.add_argument(
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"--gpu-memory-util",
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type=float,
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default=0.4,
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help="GPU memory utilization fraction (default: 0.4).",
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)
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return parser.parse_args()
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def main():
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args = parse_args()
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flexkv_config = {
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"server_recv_port": f"ipc:///tmp/flexkv_test_{os.getpid()}",
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"cache_config": {
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"enable_cpu": True,
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"num_cpu_blocks": 10240,
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},
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"num_log_interval_requests": 200,
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}
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flexkv_config_path = f"./flexkv_config_{os.getpid()}.json"
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with open(flexkv_config_path, "w") as f:
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json.dump(flexkv_config, f)
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os.environ["FLEXKV_CONFIG_PATH"] = flexkv_config_path
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try:
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_run(args)
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finally:
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if os.path.exists(flexkv_config_path):
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os.remove(flexkv_config_path)
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def _run(args):
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# Common prefix.
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prefix = (
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"You are an expert school principal, skilled in effectively managing "
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"faculty and staff. Draft 10-15 questions for a potential first grade "
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"Head Teacher for my K-12, all-girls', independent school that emphasizes "
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"community, joyful discovery, and life-long learning. The candidate is "
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"coming in for a first-round panel interview for a 8th grade Math "
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"teaching role. They have 5 years of previous teaching experience "
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"as an assistant teacher at a co-ed, public school with experience "
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"in middle school math teaching. Based on these information, fulfill "
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"the following paragraph: "
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)
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# Sample prompts.
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prompts = [
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"Hello, my name is",
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"The president of the United States is",
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"The capital of France is",
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"The future of AI is",
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]
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generating_prompts = [prefix + prompt for prompt in prompts]
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# Create a sampling params object.
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sampling_params = SamplingParams(temperature=0.0)
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kv_transfer_config = {
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"kv_connector": "FlexKVConnectorV1",
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"kv_role": "kv_both",
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}
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# Create an LLM without prefix caching as a baseline.
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regular_llm = LLM(
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model=args.model,
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enable_prefix_caching=False,
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gpu_memory_utilization=args.gpu_memory_util,
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tensor_parallel_size=args.tp_size,
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)
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print("Results without `enable_prefix_caching`")
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# ruff: noqa: E501
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# Generate texts from the prompts. The output is a list of RequestOutput
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# objects that contain the prompt, generated text, and other information.
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outputs = regular_llm.generate(generating_prompts, sampling_params)
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regular_generated_texts = []
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# Print the outputs.
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print("-" * 50)
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for output in outputs:
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prompt = output.prompt
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generated_text = output.outputs[0].text
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regular_generated_texts.append(generated_text)
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print(f"Prompt: {prompt!r}\nGenerated text: {generated_text!r}")
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print("-" * 50)
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# Destroy the LLM object and free up the GPU memory.
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del regular_llm
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cleanup_dist_env_and_memory()
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# Create an LLM with prefix caching enabled.
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prefix_cached_llm = LLM(
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model=args.model,
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enable_prefix_caching=True,
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gpu_memory_utilization=args.gpu_memory_util,
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tensor_parallel_size=args.tp_size,
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kv_transfer_config=kv_transfer_config,
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)
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# Warmup so that the shared prompt's KV cache is computed.
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prefix_cached_llm.generate(generating_prompts[0], sampling_params)
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# wait for offload kv task finished.
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time.sleep(2)
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# Generate with prefix caching.
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outputs = prefix_cached_llm.generate(generating_prompts, sampling_params)
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print("Results with `enable_prefix_caching`")
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cached_generated_texts = []
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# Print the outputs. You should see the same outputs as before.
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print("-" * 50)
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for output in outputs:
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prompt = output.prompt
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generated_text = output.outputs[0].text
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cached_generated_texts.append(generated_text)
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print(f"Prompt: {prompt!r}\nGenerated text: {generated_text!r}")
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print("-" * 50)
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# Compare the results and display the speedup
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generated_same = all(
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regular_generated_texts[i] == cached_generated_texts[i]
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for i in range(len(prompts))
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)
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print(f"Generated answers are the same: {generated_same}")
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# wait for offload kv task finished.
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time.sleep(2)
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# reset prefix cache to use flexkv
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prefix_cached_llm.reset_prefix_cache()
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# Generate with prefix caching.
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outputs = prefix_cached_llm.generate(generating_prompts, sampling_params)
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print("Results with `flexkv`")
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flexkv_generated_texts = []
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# Print the outputs. You should see the same outputs as before.
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print("-" * 50)
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for output in outputs:
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prompt = output.prompt
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generated_text = output.outputs[0].text
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flexkv_generated_texts.append(generated_text)
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print(f"Prompt: {prompt!r}\nGenerated text: {generated_text!r}")
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print("-" * 50)
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# Compare the results and display the speedup
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generated_same = all(
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regular_generated_texts[i] == flexkv_generated_texts[i]
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for i in range(len(prompts))
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)
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print(f"Generated answers are the same: {generated_same}")
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if __name__ == "__main__":
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main()
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232
tests/v1/kv_connector/unit/test_flexkv_connector.py
Normal file
232
tests/v1/kv_connector/unit/test_flexkv_connector.py
Normal file
@@ -0,0 +1,232 @@
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# SPDX-License-Identifier: Apache-2.0
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# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
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"""Unit tests for FlexKVConnectorV1.
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These tests mock the ``flexkv`` package so they can run without a real FlexKV
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installation. They verify:
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1. That ``FlexKVConnectorV1`` raises a helpful ``ImportError`` when FlexKV is
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not installed.
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2. That all public methods are correctly delegated to the underlying
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``FlexKVConnectorV1Impl``.
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"""
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import sys
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import types
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from unittest.mock import MagicMock, patch
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import pytest
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import torch
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from vllm.config import KVTransferConfig, VllmConfig
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from vllm.distributed.kv_transfer.kv_connector.v1 import KVConnectorRole
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from vllm.v1.kv_cache_interface import KVCacheConfig
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from .utils import create_vllm_config
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# ---------------------------------------------------------------------------
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# Helpers
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# ---------------------------------------------------------------------------
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def _make_vllm_config(
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kv_connector: str = "FlexKVConnectorV1",
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kv_role: str = "kv_both",
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) -> VllmConfig:
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"""Return a minimal VllmConfig with a KVTransferConfig attached."""
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vllm_config = create_vllm_config(block_size=16, max_num_batched_tokens=512)
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vllm_config.kv_transfer_config = KVTransferConfig(
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kv_connector=kv_connector,
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kv_role=kv_role,
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)
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return vllm_config
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def _make_kv_cache_config() -> KVCacheConfig:
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return MagicMock(spec=KVCacheConfig)
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def _make_flexkv_module(
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impl_mock: MagicMock,
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) -> tuple[types.ModuleType, types.ModuleType]:
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"""Build a fake ``flexkv`` package hierarchy that returns *impl_mock*
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when ``FlexKVConnectorV1Impl`` is instantiated."""
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flexkv_mod = types.ModuleType("flexkv")
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integration_mod = types.ModuleType("flexkv.integration")
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vllm_mod = types.ModuleType("flexkv.integration.vllm")
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adapter_mod = types.ModuleType("flexkv.integration.vllm.vllm_v1_adapter")
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# Make FlexKVConnectorV1Impl() return our mock instance.
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# The "# type: ignore" markers below are needed because ModuleType does
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# not declare these attributes statically; they are set dynamically.
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FlexKVConnectorV1ImplCls = MagicMock(return_value=impl_mock)
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adapter_mod.FlexKVConnectorV1Impl = FlexKVConnectorV1ImplCls # type: ignore
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flexkv_mod.integration = integration_mod # type: ignore
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integration_mod.vllm = vllm_mod # type: ignore
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vllm_mod.vllm_v1_adapter = adapter_mod # type: ignore
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return flexkv_mod, adapter_mod
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def _install_flexkv_mock(impl_mock: MagicMock):
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"""Insert fake flexkv modules into sys.modules and return a context that
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cleans them up afterwards."""
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flexkv_mod, adapter_mod = _make_flexkv_module(impl_mock)
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mods = {
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"flexkv": flexkv_mod,
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"flexkv.integration": flexkv_mod.integration,
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"flexkv.integration.vllm": flexkv_mod.integration.vllm,
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"flexkv.integration.vllm.vllm_v1_adapter": adapter_mod,
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}
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return patch.dict(sys.modules, mods)
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def _build_connector(vllm_config: VllmConfig, impl_mock: MagicMock):
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"""Instantiate FlexKVConnectorV1 with faked flexkv modules."""
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from vllm.distributed.kv_transfer.kv_connector.v1.flexkv_connector import (
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FlexKVConnectorV1,
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)
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with _install_flexkv_mock(impl_mock):
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connector = FlexKVConnectorV1(
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vllm_config=vllm_config,
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role=KVConnectorRole.WORKER,
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kv_cache_config=_make_kv_cache_config(),
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)
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return connector
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# ---------------------------------------------------------------------------
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# Tests
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# ---------------------------------------------------------------------------
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class TestFlexKVConnectorImportError:
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"""FlexKVConnectorV1 should fail with a helpful message when flexkv is
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absent."""
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def test_import_error_message(self):
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from vllm.distributed.kv_transfer.kv_connector.v1.flexkv_connector import (
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FlexKVConnectorV1,
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)
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# Ensure flexkv is NOT in sys.modules
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for key in list(sys.modules):
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if key.startswith("flexkv"):
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del sys.modules[key]
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with pytest.raises(ImportError, match="(?i)flexkv") as exc_info:
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FlexKVConnectorV1(
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vllm_config=_make_vllm_config(),
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role=KVConnectorRole.WORKER,
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kv_cache_config=_make_kv_cache_config(),
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)
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assert "https://github.com/taco-project/FlexKV" in str(exc_info.value)
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class TestFlexKVConnectorDelegation:
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"""All public API methods should be forwarded to the impl."""
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@pytest.fixture()
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def connector_and_impl(self):
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impl = MagicMock()
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cfg = _make_vllm_config()
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connector = _build_connector(cfg, impl)
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return connector, impl
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def test_shutdown(self, connector_and_impl):
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connector, impl = connector_and_impl
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connector.shutdown()
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impl.shutdown.assert_called_once()
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def test_start_load_kv(self, connector_and_impl):
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connector, impl = connector_and_impl
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ctx = MagicMock()
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connector.start_load_kv(ctx, extra_arg="x")
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impl.start_load_kv.assert_called_once_with(ctx, extra_arg="x")
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def test_save_kv_layer(self, connector_and_impl):
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connector, impl = connector_and_impl
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kv_layer = torch.zeros(4, 4)
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attn_meta = MagicMock()
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connector.save_kv_layer("layer_0", kv_layer, attn_meta)
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impl.save_kv_layer.assert_called_once_with("layer_0", kv_layer, attn_meta)
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def test_wait_for_save(self, connector_and_impl):
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connector, impl = connector_and_impl
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connector.wait_for_save()
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impl.wait_for_save.assert_called_once()
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def test_get_finished(self, connector_and_impl):
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connector, impl = connector_and_impl
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impl.get_finished.return_value = ({"req1"}, None)
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result = connector.get_finished({"req1"})
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impl.get_finished.assert_called_once_with({"req1"})
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assert result == ({"req1"}, None)
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def test_register_kv_caches(self, connector_and_impl):
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connector, impl = connector_and_impl
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kv_caches = {"layer_0": torch.zeros(1)}
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connector.register_kv_caches(kv_caches)
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impl.register_kv_caches.assert_called_once_with(kv_caches)
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def test_get_num_new_matched_tokens(self, connector_and_impl):
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connector, impl = connector_and_impl
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req = MagicMock()
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impl.get_num_new_matched_tokens.return_value = (10, False)
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result = connector.get_num_new_matched_tokens(req, 5)
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impl.get_num_new_matched_tokens.assert_called_once_with(req, 5)
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assert result == (10, False)
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def test_update_state_after_alloc(self, connector_and_impl):
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connector, impl = connector_and_impl
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req = MagicMock()
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blocks = MagicMock()
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connector.update_state_after_alloc(req, blocks, 4)
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impl.update_state_after_alloc.assert_called_once_with(req, blocks, 4)
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def test_build_connector_meta(self, connector_and_impl):
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connector, impl = connector_and_impl
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sched_out = MagicMock()
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connector.build_connector_meta(sched_out)
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impl.build_connector_meta.assert_called_once_with(sched_out)
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def test_update_connector_output(self, connector_and_impl):
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connector, impl = connector_and_impl
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out = MagicMock()
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connector.update_connector_output(out)
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impl.update_connector_output.assert_called_once_with(out)
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def test_request_finished(self, connector_and_impl):
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connector, impl = connector_and_impl
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req = MagicMock()
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impl.request_finished.return_value = (True, {"key": "val"})
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result = connector.request_finished(req, [1, 2, 3])
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impl.request_finished.assert_called_once_with(req, [1, 2, 3])
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assert result == (True, {"key": "val"})
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def test_take_events(self, connector_and_impl):
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connector, impl = connector_and_impl
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impl.take_events.return_value = iter([])
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list(connector.take_events())
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impl.take_events.assert_called_once()
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|
||||
def test_get_kv_connector_stats(self, connector_and_impl):
|
||||
connector, impl = connector_and_impl
|
||||
impl.get_kv_connector_stats.return_value = None
|
||||
result = connector.get_kv_connector_stats()
|
||||
impl.get_kv_connector_stats.assert_called_once()
|
||||
assert result is None
|
||||
|
||||
def test_get_block_ids_with_load_errors(self, connector_and_impl):
|
||||
connector, impl = connector_and_impl
|
||||
impl.get_block_ids_with_load_errors.return_value = {7, 8}
|
||||
result = connector.get_block_ids_with_load_errors()
|
||||
assert result == {7, 8}
|
||||
|
||||
def test_wait_for_layer_load(self, connector_and_impl):
|
||||
connector, impl = connector_and_impl
|
||||
connector.wait_for_layer_load("layer_0")
|
||||
impl.wait_for_layer_load.assert_called_once_with("layer_0")
|
||||
@@ -207,3 +207,9 @@ KVConnectorFactory.register_connector(
|
||||
"vllm.distributed.kv_transfer.kv_connector.v1.mooncake.mooncake_connector",
|
||||
"MooncakeConnector",
|
||||
)
|
||||
|
||||
KVConnectorFactory.register_connector(
|
||||
"FlexKVConnectorV1",
|
||||
"vllm.distributed.kv_transfer.kv_connector.v1.flexkv_connector",
|
||||
"FlexKVConnectorV1",
|
||||
)
|
||||
|
||||
260
vllm/distributed/kv_transfer/kv_connector/v1/flexkv_connector.py
Normal file
260
vllm/distributed/kv_transfer/kv_connector/v1/flexkv_connector.py
Normal file
@@ -0,0 +1,260 @@
|
||||
# SPDX-License-Identifier: Apache-2.0
|
||||
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
|
||||
from collections.abc import Iterable
|
||||
from typing import TYPE_CHECKING, Any
|
||||
|
||||
import torch
|
||||
|
||||
from vllm.config import VllmConfig
|
||||
from vllm.distributed.kv_transfer.kv_connector.v1.base import (
|
||||
KVConnectorBase_V1,
|
||||
KVConnectorMetadata,
|
||||
KVConnectorRole,
|
||||
)
|
||||
from vllm.distributed.kv_transfer.kv_connector.v1.metrics import KVConnectorStats
|
||||
from vllm.logger import init_logger
|
||||
from vllm.v1.core.sched.output import SchedulerOutput
|
||||
from vllm.v1.outputs import KVConnectorOutput
|
||||
|
||||
if TYPE_CHECKING:
|
||||
from vllm.distributed.kv_events import KVCacheEvent
|
||||
from vllm.forward_context import ForwardContext
|
||||
from vllm.v1.attention.backend import AttentionMetadata
|
||||
from vllm.v1.core.kv_cache_manager import KVCacheBlocks
|
||||
from vllm.v1.kv_cache_interface import KVCacheConfig
|
||||
from vllm.v1.request import Request
|
||||
|
||||
logger = init_logger(__name__)
|
||||
|
||||
|
||||
# FlexKV is a distributed KV Store and multi-level cache management system for
|
||||
# ultra-large-scale LLM inference.
|
||||
# GitHub: https://github.com/taco-project/FlexKV
|
||||
# Install: git clone git@github.com:taco-project/FlexKV.git \
|
||||
# && cd FlexKV && bash build.sh
|
||||
class FlexKVConnectorV1(KVConnectorBase_V1):
|
||||
"""KV Connector that offloads KV cache to FlexKV.
|
||||
|
||||
FlexKV is a distributed KV Store and multi-level cache management system
|
||||
designed for ultra-large-scale LLM inference. It supports offloading KV
|
||||
cache to CPU memory, SSD, and remote storage.
|
||||
|
||||
Installation:
|
||||
See https://github.com/taco-project/FlexKV for installation instructions.
|
||||
Quick start::
|
||||
|
||||
git clone git@github.com:taco-project/FlexKV.git
|
||||
cd FlexKV && bash build.sh
|
||||
|
||||
Configuration:
|
||||
Pass ``kv_connector="FlexKVConnectorV1"`` via ``--kv-transfer-config``::
|
||||
|
||||
--kv-transfer-config \
|
||||
'{"kv_connector":"FlexKVConnectorV1","kv_role":"kv_both"}'
|
||||
"""
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
vllm_config: "VllmConfig",
|
||||
role: KVConnectorRole,
|
||||
kv_cache_config: "KVCacheConfig",
|
||||
):
|
||||
super().__init__(
|
||||
vllm_config=vllm_config, role=role, kv_cache_config=kv_cache_config
|
||||
)
|
||||
try:
|
||||
from flexkv.integration.vllm.vllm_v1_adapter import FlexKVConnectorV1Impl
|
||||
except ImportError as e:
|
||||
raise ImportError(
|
||||
"FlexKV is not installed. Please install it to use "
|
||||
"FlexKVConnectorV1. See https://github.com/taco-project/FlexKV "
|
||||
"for installation instructions."
|
||||
) from e
|
||||
|
||||
self._flexkv_connector = FlexKVConnectorV1Impl(vllm_config, role)
|
||||
|
||||
def shutdown(self):
|
||||
self._flexkv_connector.shutdown()
|
||||
|
||||
# ==============================
|
||||
# Worker-side methods
|
||||
# ==============================
|
||||
def start_load_kv(self, forward_context: "ForwardContext", **kwargs) -> None:
|
||||
"""No-op for FlexKV (currently).
|
||||
|
||||
FlexKV manages all KV transfers on the **scheduler side** via
|
||||
``build_connector_meta`` (which calls ``launch_tasks``) and
|
||||
``update_connector_output`` (which polls ``query_finished_task``).
|
||||
KV blocks are transferred directly between the FlexKV server and
|
||||
vLLM's GPU memory without worker-side intervention during the
|
||||
forward pass — similar to how NIXL operates.
|
||||
|
||||
These worker-side hooks are kept (rather than omitted) to satisfy
|
||||
the ``KVConnectorBase_V1`` interface contract and to serve as
|
||||
extension points for a future worker-side layer-pipelining path.
|
||||
|
||||
Args:
|
||||
forward_context (ForwardContext): the forward context.
|
||||
**kwargs (Any): additional arguments (unused).
|
||||
"""
|
||||
self._flexkv_connector.start_load_kv(forward_context, **kwargs)
|
||||
|
||||
def wait_for_layer_load(self, layer_name: str) -> None:
|
||||
"""No-op for FlexKV (currently).
|
||||
|
||||
FlexKV manages all KV transfers on the scheduler side.
|
||||
This hook is retained for ``KVConnectorBase_V1`` API compatibility.
|
||||
|
||||
Args:
|
||||
layer_name: the name of the layer (unused).
|
||||
"""
|
||||
self._flexkv_connector.wait_for_layer_load(layer_name)
|
||||
|
||||
def save_kv_layer(
|
||||
self,
|
||||
layer_name: str,
|
||||
kv_layer: torch.Tensor,
|
||||
attn_metadata: "AttentionMetadata",
|
||||
**kwargs,
|
||||
) -> None:
|
||||
"""No-op for FlexKV (currently).
|
||||
|
||||
FlexKV offloads KV cache asynchronously from the scheduler side
|
||||
after a request finishes (see ``request_finished``). It does not
|
||||
intercept individual layer tensors during the forward pass.
|
||||
|
||||
This hook is retained to satisfy ``KVConnectorBase_V1`` and as an
|
||||
extension point for future per-layer async offload support.
|
||||
|
||||
Args:
|
||||
layer_name (str): the name of the layer (unused).
|
||||
kv_layer (torch.Tensor): the paged KV buffer (unused).
|
||||
attn_metadata (AttentionMetadata): the attention metadata (unused).
|
||||
**kwargs (Any): additional arguments (unused).
|
||||
"""
|
||||
self._flexkv_connector.save_kv_layer(
|
||||
layer_name, kv_layer, attn_metadata, **kwargs
|
||||
)
|
||||
|
||||
def wait_for_save(self):
|
||||
"""No-op for FlexKV (currently).
|
||||
|
||||
KV offload tasks are tracked asynchronously by the scheduler
|
||||
connector via ``request_finished`` / ``query_finished_task``.
|
||||
There is no pending worker-side save to wait for at
|
||||
forward-context exit.
|
||||
|
||||
Retained to satisfy ``KVConnectorBase_V1`` and as an extension
|
||||
point for future worker-side save-completion signalling.
|
||||
"""
|
||||
self._flexkv_connector.wait_for_save()
|
||||
|
||||
def get_finished(
|
||||
self, finished_req_ids: set[str]
|
||||
) -> tuple[set[str] | None, set[str] | None]:
|
||||
"""Notify worker-side connector of requests that have finished
|
||||
generating tokens.
|
||||
|
||||
Returns:
|
||||
Tuple of (sending/saving ids, recving/loading ids) for requests
|
||||
that have finished asynchronous transfer. The finished saves/sends
|
||||
req ids must belong to a set provided in a call to this method
|
||||
(this call or a prior one).
|
||||
"""
|
||||
return self._flexkv_connector.get_finished(finished_req_ids)
|
||||
|
||||
def register_kv_caches(self, kv_caches: dict[str, torch.Tensor]):
|
||||
"""Initialize with the KV caches. Useful for pre-registering the
|
||||
KV caches in the KVConnector (e.g. for NIXL).
|
||||
|
||||
Args:
|
||||
kv_caches: dictionary of layer names to kv cache tensors.
|
||||
"""
|
||||
self._flexkv_connector.register_kv_caches(kv_caches)
|
||||
|
||||
# ==============================
|
||||
# Scheduler-side methods
|
||||
# ==============================
|
||||
def get_num_new_matched_tokens(
|
||||
self,
|
||||
request: "Request",
|
||||
num_computed_tokens: int,
|
||||
) -> tuple[int, bool]:
|
||||
"""Get the number of new tokens that can be loaded from the
|
||||
external KV cache beyond ``num_computed_tokens``.
|
||||
|
||||
Args:
|
||||
request (Request): the request object.
|
||||
num_computed_tokens (int): the number of locally computed
|
||||
tokens for this request.
|
||||
|
||||
Returns:
|
||||
Tuple of (num_external_tokens, is_ready) where
|
||||
num_external_tokens is the number of additional tokens that
|
||||
can be loaded from the external KV cache.
|
||||
"""
|
||||
return self._flexkv_connector.get_num_new_matched_tokens(
|
||||
request, num_computed_tokens
|
||||
)
|
||||
|
||||
def update_state_after_alloc(
|
||||
self, request: "Request", blocks: "KVCacheBlocks", num_external_tokens: int
|
||||
):
|
||||
"""Update KVConnector state after block allocation."""
|
||||
self._flexkv_connector.update_state_after_alloc(
|
||||
request, blocks, num_external_tokens
|
||||
)
|
||||
|
||||
def build_connector_meta(
|
||||
self, scheduler_output: SchedulerOutput
|
||||
) -> KVConnectorMetadata:
|
||||
"""Build the connector metadata for this step.
|
||||
|
||||
This function should NOT modify fields in the scheduler_output.
|
||||
Also, calling this function will reset the state of the connector.
|
||||
|
||||
Args:
|
||||
scheduler_output (SchedulerOutput): the scheduler output object.
|
||||
"""
|
||||
return self._flexkv_connector.build_connector_meta(scheduler_output)
|
||||
|
||||
def update_connector_output(self, connector_output: KVConnectorOutput):
|
||||
"""Update KVConnector state from worker-side connectors output.
|
||||
|
||||
Args:
|
||||
connector_output (KVConnectorOutput): the worker-side
|
||||
connectors output.
|
||||
"""
|
||||
self._flexkv_connector.update_connector_output(connector_output)
|
||||
|
||||
def request_finished(
|
||||
self,
|
||||
request: "Request",
|
||||
block_ids: list[int],
|
||||
) -> tuple[bool, dict[str, Any] | None]:
|
||||
"""Called when a request has finished, before its blocks are freed.
|
||||
|
||||
Returns:
|
||||
Tuple of (async_save, kv_transfer_params) where async_save is
|
||||
True if the request is being saved/sent asynchronously and blocks
|
||||
should not be freed until the request_id is returned from
|
||||
:meth:`get_finished`. kv_transfer_params is an optional dict of
|
||||
KVTransferParams to be included in the request outputs.
|
||||
"""
|
||||
return self._flexkv_connector.request_finished(request, block_ids)
|
||||
|
||||
def take_events(self) -> Iterable["KVCacheEvent"]:
|
||||
"""Collect buffered KV cache events.
|
||||
|
||||
Returns:
|
||||
New KV cache events since the last call.
|
||||
"""
|
||||
return self._flexkv_connector.take_events()
|
||||
|
||||
def get_kv_connector_stats(self) -> KVConnectorStats | None:
|
||||
"""Get the KV connector stats collected during the last interval."""
|
||||
return self._flexkv_connector.get_kv_connector_stats()
|
||||
|
||||
def get_block_ids_with_load_errors(self) -> set[int]:
|
||||
"""Get the block ids that have failed to load."""
|
||||
return self._flexkv_connector.get_block_ids_with_load_errors()
|
||||
Reference in New Issue
Block a user