ggml-zendnn : add ZenDNN backend for AMD CPUs

README.md

@@ -276,6 +276,7 @@ Instructions for adding support for new models: [HOWTO-add-model.md](docs/develo
 | [MUSA](docs/build.md#musa) | Moore Threads GPU |
 | [CUDA](docs/build.md#cuda) | Nvidia GPU |
 | [HIP](docs/build.md#hip) | AMD GPU |
+| [ZenDNN](docs/build.md#zendnn) | AMD CPU |
 | [Vulkan](docs/build.md#vulkan) | GPU |
 | [CANN](docs/build.md#cann) | Ascend NPU |
 | [OpenCL](docs/backend/OPENCL.md) | Adreno GPU |

docs/backend/ZenDNN.md

@@ -0,0 +1,257 @@
+# llama.cpp for AMD ZenDNN
+
+> **Note:** ZenDNN is **not** the same as zDNN.
+> - **ZenDNN** (this page): AMD's deep learning library for AMD EPYC CPUs
+> - **zDNN**: IBM's library for IBM Z mainframe processors ([see zDNN documentation](zDNN.md))
+
+- [Background](#background)
+- [OS](#os)
+- [Hardware](#hardware)
+- [Supported Operations](#supported-operations)
+- [DataType Supports](#datatype-supports)
+- [Linux](#linux)
+- [Environment Variable](#environment-variable)
+- [Performance Optimization](#performance-optimization)
+- [Known Issues](#known-issues)
+- [TODO](#todo)
+
+## Background
+
+**ZenDNN** (Zen Deep Neural Network Library) is AMD's high-performance deep learning inference library optimized for AMD EPYC™ CPUs. It provides optimized implementations of key deep learning primitives and operations, delivering significant performance improvements for neural network workloads on AMD Zen-based processor architectures.
+
+**Llama.cpp + ZenDNN**
+
+The llama.cpp ZenDNN backend leverages AMD's optimized matrix multiplication primitives to accelerate inference on AMD CPUs. It utilizes ZenDNN's **LowOHA (Low Overhead Hardware Accelerated)** MatMul operator for efficient GEMM operations with minimal execution overhead, built-in weight caching, and direct access to backend libraries (AOCL BLIS, LibXSMM, OneDNN).
+
+For more information about ZenDNN, visit: https://www.amd.com/en/developer/zendnn.html
+
+## OS
+
+| OS      | Status  | Verified                                       |
+|:-------:|:-------:|:----------------------------------------------:|
+| Linux   | Support | Ubuntu 20.04, 22.04, 24.04                     |
+
+For the latest list of supported operating systems, see the [ZenDNN Supported OS](https://github.com/amd/ZenDNN/blob/zendnnl/README.md#15-supported-os).
+
+## Hardware
+
+### AMD CPUs
+
+**Recommended Processors**
+
+ZenDNN is optimized for AMD EPYC™ processors and AMD Ryzen™ processors based on "Zen" microarchitecture and newer.
+
+| CPU Family                    | Status  | Notes                              |
+|:-----------------------------:|:-------:|:----------------------------------:|
+| AMD EPYC™ 9005 Series (Turin)| Support | 5th Gen - Zen 5 architecture       |
+| AMD EPYC™ 9004 Series (Genoa)| Support | 4th Gen - Zen 4 architecture       |
+| AMD EPYC™ 7003 Series (Milan)| Support | 3rd Gen - Zen 3 architecture       |
+| AMD Ryzen™ AI MAX (Strix Halo)| Support | High-performance mobile processors |
+
+*Notes:*
+
+- Best performance is achieved on AMD EPYC™ processors with high core counts (e.g., EPYC 9005 series).
+- ZenDNN leverages AMD's advanced CPU features including AVX2 and AVX-512 instruction sets.
+- For optimal performance, ensure your system has sufficient memory bandwidth.
+
+## Supported Operations
+
+The ZenDNN backend currently accelerates **matrix multiplication (MUL_MAT)** operations only. Other operations are handled by the standard CPU backend.
+
+| Operation    | Status  | Notes                                          |
+|:-------------|:-------:|:----------------------------------------------:|
+| MUL_MAT      |    ✓    | Accelerated via ZenDNN LowOHA MatMul           |
+
+*Note:* Since only MUL_MAT is accelerated, models will benefit most from ZenDNN when matrix multiplications dominate the computational workload (which is typical for transformer-based LLMs).
+
+## DataType Supports
+
+| DataType               | Status  | Notes                                         |
+|:----------------------:|:-------:|:---------------------------------------------:|
+| FP32                   | Support | Full precision floating point                 |
+| BF16                   | Support | BFloat16 (best performance on Zen 4/Zen 5)    |
+
+*Notes:*
+
+- **BF16** provides best performance on Zen 4 and Zen 5 EPYC™ processors (Genoa, Turin).
+
+## Linux
+
+### I. Setup Environment
+
+You have two options to set up ZenDNN:
+
+#### Option 1: Automatic Download and Build (Recommended)
+
+CMake will automatically download and build ZenDNN for you:
+
+```sh
+# Build llama.cpp - ZenDNN will be automatically downloaded and built
+cmake -B build -DGGML_ZENDNN=ON -DCMAKE_BUILD_TYPE=Release
+cmake --build build --config Release -j $(nproc)
+```
+
+No manual ZenDNN installation required. CMake will handle everything automatically.
+
+#### Option 2: Use Custom ZenDNN Installation
+
+If you want to build ZenDNN yourself or use a specific version:
+
+**Step 1: Build ZenDNN from source**
+
+```sh
+# Clone ZenDNN repository
+git clone https://github.com/amd/ZenDNN.git
+cd ZenDNN
+git checkout zendnnl
+
+# Build and install (requires CMake >= 3.25)
+mkdir build && cd build
+cmake ..
+cmake --build . --target all
+```
+
+Default installation path: `ZenDNN/build/install`
+
+**For detailed build instructions**, refer to the [ZenDNN README](https://github.com/amd/ZenDNN/blob/zendnnl/README.md).
+
+**Step 2: Build llama.cpp with custom ZenDNN path**
+
+```sh
+# Using environment variable
+export ZENDNN_ROOT=/path/to/ZenDNN/build/install
+cmake -B build -DGGML_ZENDNN=ON -DCMAKE_BUILD_TYPE=Release
+cmake --build build --config Release -j $(nproc)
+
+# OR specify path directly in CMake
+cmake -B build -DGGML_ZENDNN=ON -DZENDNN_ROOT=/path/to/ZenDNN/build/install -DCMAKE_BUILD_TYPE=Release
+cmake --build build --config Release -j $(nproc)
+```
+
+### II. Run the Server
+
+#### 1. Download Model
+
+Download LLaMA 3.1 8B Instruct BF16 model:
+
+```sh
+# Download from Hugging Face
+huggingface-cli download meta-llama/Llama-3.1-8B-Instruct-GGUF --local-dir models/
+```
+
+#### 2. Start Server
+
+Run llama.cpp server with ZenDNN acceleration:
+
+```sh
+# Set optimal configuration
+export OMP_NUM_THREADS=64  # Adjust to your CPU core count
+export ZENDNNL_MATMUL_ALGO=2  # Blocked AOCL BLIS for best performance
+
+# Start server
+./build/bin/llama-server \
+    -m models/Llama-3.1-8B-Instruct.BF16.gguf \
+    --host 0.0.0.0 \
+    --port 8080 \
+    -t 64
+```
+
+Access the server at `http://localhost:8080`.
+
+**Performance tips**:
+- Set `OMP_NUM_THREADS` to match your physical core count
+- Use `ZENDNNL_MATMUL_ALGO=2` for optimal performance
+- For NUMA systems: `numactl --cpunodebind=0 --membind=0 ./build/bin/llama-server ...`
+
+## Environment Variable
+
+### Build Time
+
+| Name               | Value                                 | Function                                    |
+|--------------------|---------------------------------------|---------------------------------------------|
+| GGML_ZENDNN        | ON/OFF                                | Enable ZenDNN backend support               |
+| ZENDNN_ROOT        | Path to ZenDNN installation           | Set ZenDNN installation directory           |
+| GGML_OPENMP        | ON/OFF (recommended: ON)              | Enable OpenMP for multi-threading           |
+
+### Runtime
+
+| Name                    | Value                    | Function                                                          |
+|-------------------------|--------------------------|-------------------------------------------------------------------|
+| OMP_NUM_THREADS         | Number (e.g., 64)        | Set number of OpenMP threads (recommended: physical core count)   |
+| ZENDNNL_MATMUL_ALGO     | 0-5                      | Select MatMul backend algorithm (see Performance Optimization)    |
+| ZENDNNL_PROFILE_LOG_LEVEL | 0-4                    | Profiling log level (0=disabled, 4=verbose)                       |
+| ZENDNNL_ENABLE_PROFILER | 0 or 1                   | Enable detailed profiling (1=enabled)                             |
+| ZENDNNL_API_LOG_LEVEL   | 0-4                      | API log level (0=disabled, 4=verbose)                             |
+
+**Example**:
+
+```sh
+export OMP_NUM_THREADS=64
+export ZENDNNL_MATMUL_ALGO=2  # Use Blocked AOCL BLIS for best performance
+./build/bin/llama-cli -m models/llama-2-7b.Q4_0.gguf -p "Test" -n 100
+```
+
+## Performance Optimization
+
+### MatMul Algorithm Selection
+
+ZenDNN's LowOHA MatMul supports multiple backend algorithms. For **best performance**, use the **Blocked AOCL BLIS** algorithm:
+
+```sh
+export ZENDNNL_MATMUL_ALGO=2  # Blocked AOCL BLIS (recommended)
+```
+
+**Available algorithms**:
+
+| Value | Algorithm              | Description                                    |
+|:-----:|:-----------------------|:----------------------------------------------|
+| 0     | Dynamic Dispatch       | Automatic backend selection (default)         |
+| 1     | AOCL BLIS              | AOCL BLIS backend                             |
+| 2     | AOCL BLIS Blocked      | **Blocked AOCL BLIS (recommended)**           |
+| 3     | OneDNN                 | OneDNN backend                                |
+| 4     | OneDNN Blocked         | Blocked OneDNN                                |
+| 5     | LibXSMM                | LibXSMM backend                               |
+
+### Profiling and Debugging
+
+For detailed profiling and logging options, refer to the [ZenDNN Logging Documentation](https://github.com/amd/ZenDNN/blob/zendnnl/docs/logging.md).
+
+## Known Issues
+
+- **Limited operation support**: Currently only matrix multiplication (MUL_MAT) is accelerated via ZenDNN. Other operations fall back to the standard CPU backend.
+- **BF16 support**: BF16 operations require AMD Zen 4 or Zen 5 architecture (EPYC 9004/9005 series). On older CPUs, operations will use FP32.
+- **NUMA awareness**: For multi-socket systems, manual NUMA binding may be required for optimal performance.
+
+## Q&A
+
+**Q: How do I verify that ZenDNN backend is being used?**
+
+A: Check the log output when running llama.cpp. You should see messages indicating the ZenDNN backend is initialized. You can also check the backend name in the output.
+
+**Q: What performance improvement can I expect?**
+
+A: Performance gains vary depending on the model size, batch size, and CPU architecture. On AMD EPYC processors, you can typically expect 1.1x-2x speedup compared to standard CPU inference for matrix multiplication operations.
+
+**Q: Can I use ZenDNN on non-AMD processors?**
+
+A: ZenDNN is optimized specifically for AMD processors. While it may work on other x86-64 CPUs, performance benefits are only guaranteed on AMD Zen-based architectures.
+
+**Q: Does ZenDNN support quantized models?**
+
+A: Currently, ZenDNN primarily supports FP32 and BF16 data types. Quantized model support is not available at this time.
+
+**Q: Why is my inference not faster with ZenDNN?**
+
+A: Ensure:
+1. You're using an AMD EPYC or Ryzen processor (Zen 2 or newer)
+2. `OMP_NUM_THREADS` is set appropriately (physical core count)
+3. `ZENDNNL_MATMUL_ALGO=2` is set for best performance (Blocked AOCL BLIS)
+4. You're using a sufficiently large model (small models may not benefit as much)
+5. Enable profiling to verify ZenDNN MatMul is being called
+
+### **GitHub Contribution**:
+Please add the **[ZenDNN]** prefix/tag in issues/PRs titles to help the ZenDNN-team check/address them without delay.
+
+## TODO
+
+- Expand operation support beyond MUL_MAT (attention operations, activations, etc.)

docs/backend/zDNN.md

@@ -1,5 +1,9 @@
 # llama.cpp for IBM zDNN Accelerator
 
+> **Note:** zDNN is **not** the same as ZenDNN.
+> - **zDNN** (this page): IBM's library for IBM Z mainframe processors
+> - **ZenDNN**: AMD's deep learning library for AMD EPYC CPUs ([see ZenDNN documentation](ZenDNN.md))
+
 ## Background
 
 IBM zDNN (Z Deep Neural Network) is a hardware acceleration library designed specifically to leverage the IBM NNPA (Neural Network Processor Assist) accelerator located within IBM Telum I and II processors. It provides significant performance improvements for neural network inference operations.

docs/build.md

@@ -484,6 +484,38 @@ llama_new_context_with_model:       CANN compute buffer size =  1260.81 MiB
 
 For detailed info, such as model/device supports, CANN install, please refer to [llama.cpp for CANN](./backend/CANN.md).
 
+## ZenDNN
+
+ZenDNN provides optimized deep learning primitives for AMD EPYC™ CPUs. It accelerates matrix multiplication operations for inference workloads.
+
+### Compilation
+
+- Using `CMake` on Linux (automatic build):
+
+    ```bash
+    cmake -B build -DGGML_ZENDNN=ON
+    cmake --build build --config Release
+    ```
+
+    The first build will automatically download and build ZenDNN, which may take 5-10 minutes. Subsequent builds will be much faster.
+
+- Using `CMake` with custom ZenDNN installation:
+
+    ```bash
+    cmake -B build -DGGML_ZENDNN=ON -DZENDNN_ROOT=/path/to/zendnn/install
+    cmake --build build --config Release
+    ```
+
+### Testing
+
+You can test with:
+
+```bash
+./build/bin/llama-cli -m PATH_TO_MODEL -p "Building a website can be done in 10 steps:" -n 50
+```
+
+For detailed information about hardware support, setup instructions, and performance optimization, refer to [llama.cpp for ZenDNN](./backend/ZenDNN.md).
+
 ## Arm® KleidiAI™
 KleidiAI is a library of optimized microkernels for AI workloads, specifically designed for Arm CPUs. These microkernels enhance performance and can be enabled for use by the CPU backend.