Sunrise Link Transport

Overview

Sunrise Link is a GPU transport backend in the Mooncake TENT transfer framework. It relies on Tang Runtime (tangrt) for device memory allocation, pointer attribute queries, peer copy, and IPC handle operations, and is registered as SUNRISE_LINK in TENT.

At runtime, TransferEngineImpl loads Sunrise Link Transport when USE_SUNRISE is enabled at build time and transports/sunrise_link/enable=true is set in config.

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Additional Dependencies

In addition to Mooncake’s base dependencies, Sunrise Link Transport requires Tang Runtime:

• Header path: /usr/local/tangrt/include

• Library path: /usr/local/tangrt/lib/linux-x86_64

• Shared library: libtangrt_shared.so (loaded from the default installation path at runtime)

Make sure runtime libraries related to tangrt and ptml can be found by the dynamic linker (for example, via LD_LIBRARY_PATH or system library search paths).

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Build and Compile

Prerequisites

• Tang Runtime is installed and available (default path: /usr/local/tangrt)

• Build environment can access Mooncake and its base dependencies

CMake Configuration

# Clone Mooncake
git clone https://github.com/kvcache-ai/Mooncake.git
cd Mooncake

# Enable TENT + Sunrise Link
mkdir build && cd build
cmake .. -DUSE_TENT=ON -DUSE_SUNRISE=ON

# Build
make -j$(nproc)

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Run and Test

transfer_engine_bench supports the sunrise_link protocol for basic connectivity and performance validation.

# Terminal 1: target
./transfer_engine_bench \
  --mode=target \
  --protocol=sunrise_link \
  --local_server_name=10.0.0.2 \
  --metadata_server=P2PHANDSHAKE \
  --gpu_id=0

# Terminal 2: initiator
./transfer_engine_bench \
  --mode=initiator \
  --protocol=sunrise_link \
  --metadata_server=P2PHANDSHAKE \
  --segment_id=10.0.0.2:$PORT \
  --gpu_id=0 \
  --block_size=8388608 \
  --batch_size=32

Note: when metadata_server=P2PHANDSHAKE, the target node may listen on a dynamically assigned port. Replace $PORT in --segment_id with the actual port printed in target logs.

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Configuration Options (TENT)

Sunrise Link behavior can be tuned through config file options:

• transports/sunrise_link/enable: enable or disable the transport (default: true)

• transports/sunrise_link/async_memcpy_threshold: threshold for async memcpy (MiB)

Tune these options based on workload characteristics and hardware topology.