Checklist

• 1. I have searched related issues but cannot get the expected help.
• 2. The bug has not been fixed in the latest version.
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Describe the bug

Hello,

I was able to successfully setup mooncake backend for hicache.
Then I tried to run the test as was proposed in the instruction but it failed with

AttributeError: 'MooncakeStore' object has no attribute 'register_buffer'

I guess MooncakeStore changed but test_mooncake_store.py was not updated accordingly.

Reproduction

mooncake_master --enable_http_metadata_server=true --eviction_high_watermark_ratio=0.95

and then

MOONCAKE_TE_META_DATA_SERVER="http://127.0.0.1:8080/metadata" \
MOONCAKE_MASTER=127.0.0.1:50051 \
MOONCAKE_PROTOCOL="tcp" \
MOONCAKE_GLOBAL_SEGMENT_SIZE=16777216 \
python3 [path of test_mooncake_store.py]

as described in the readme

Environment

Python: 3.12.12 | packaged by conda-forge | (main, Oct 22 2025, 23:25:55) [GCC 14.3.0]
CUDA available: True
GPU 0,1,2,3: NVIDIA H100 80GB HBM3
GPU 0,1,2,3 Compute Capability: 9.0
CUDA_HOME: /usr/local/cuda-12.9
NVCC: Cuda compilation tools, release 12.9, V12.9.86
CUDA Driver Version: 580.95.05
PyTorch: 2.8.0+cu128
sglang: 0.5.5.post2
sgl_kernel: 0.3.17
flashinfer_python: 0.5.0
flashinfer_cubin: 0.5.0
flashinfer_jit_cache: Module Not Found
triton: 3.4.0
transformers: 4.57.1
torchao: 0.9.0
numpy: 2.3.4
aiohttp: 3.13.2
fastapi: 0.121.2
hf_transfer: 0.1.9
huggingface_hub: 0.36.0
interegular: 0.3.3
modelscope: 1.31.0
orjson: 3.11.4
outlines: 0.1.11
packaging: 25.0
psutil: 7.1.3
pydantic: 2.12.4
python-multipart: 0.0.20
pyzmq: 27.1.0
uvicorn: 0.38.0
uvloop: 0.21.0
vllm: Module Not Found
xgrammar: 0.1.25
openai: 2.6.1
tiktoken: 0.12.0
anthropic: 0.73.0
litellm: Module Not Found
decord2: 2.0.0
NVIDIA Topology:
�[4mGPU0 GPU1 GPU2 GPU3 CPU Affinity NUMA Affinity GPU NUMA ID�[0m
GPU0 X NV6 NV6 NV6 0-31,128-159 0 N/A
GPU1 NV6 X NV6 NV6 0-31,128-159 0 N/A
GPU2 NV6 NV6 X NV6 64-95,192-223 2 N/A
GPU3 NV6 NV6 NV6 X 64-95,192-223 2 N/A

Legend:

X = Self
SYS = Connection traversing PCIe as well as the SMP interconnect between NUMA nodes (e.g., QPI/UPI)
NODE = Connection traversing PCIe as well as the interconnect between PCIe Host Bridges within a NUMA node
PHB = Connection traversing PCIe as well as a PCIe Host Bridge (typically the CPU)
PXB = Connection traversing multiple PCIe bridges (without traversing the PCIe Host Bridge)
PIX = Connection traversing at most a single PCIe bridge
NV# = Connection traversing a bonded set of # NVLinks

ulimit soft: 1024