AMD Instinct MI300A APU With CDNA 3 GPU, Zen 4 CPU & Unified Memory Offers Up To 4x Speedup Versus Discrete GPUs In HPC

04.05.2024 - 16:19 / wccftech.com / Hassan Mujtaba

AMD's Instinct MI300A APUs deliver a substantial performance improvement in HPC workloads versus traditional discrete GPUs.

Step Aside Discrete GPUs, AMD's Instinct MI300A APUs Are Going To Supercharge HPC Workloads With Up To 4x Performance

The AMD Instinct MI300A is the realization of the "Exascale APU" platform that was laid out years ago. The idea was to package a high-performance GPU alongside a high-performance CPU on the same package which harnesses a unified memory pool. For HPC, these accelerators/co-processor designs provide higher performance per watt advantages but require a lot of porting, tuning, and maintaining applications with millions of lines of code which can be a bit complicated. However, it looks like researchers have used two popular programming models, OpenMP and OpenACC, to fully utilize AMD's next-gen APU juggernaut.

Related Story AMD Talks AI Capabilities of RDNA 3 GPUs & XDNA NPU: Radeon RX 7900 XT Up To 8X Faster Than Ryzen 7 8700G

For this research paper, titled "Porting HPC Applications to AMD Instinct MI300A Using Unified Memory and OpenMP", the OpenFOAM framework is used, which is an open-source C++ library:

• We provide a blueprint of the APU programming model and demonstrate the ease and flexibility of porting codes on MI300A with OpenMP.
• We elaborate our method for incremental acceleration of production and widely used in industry code—OpenFOAM.

Since the AMD Instinct MI300A accelerator uses a unified HBM interface, it eliminates the need for data replication and does not require a programming distinction between the host and the device memory spaces. Furthermore, AMD's ROCm software suite provides additional optimizations that help combine all segments of the APU in one coherent and heterogeneous package. As a tiny bit of a recap on AMD's Instinct MI300A APUs:

• First Integrated CPU+GPU Package
• Aiming Exascale Supercomputer Market
• AMD MI300A (Integrated CPU + GPU)
• 153 Billion Transistors
• Up To 24 Zen 4 Cores
• CDNA 3 GPU Architecture
• Up To 192 GB HBM3 Memory
• Up To 8 Chiplets + 8 Memory Stacks (5nm + 6nm process)

As a result, the performance gets a huge benefit. In the evaluation using OpenFOAM's HPC motor bike benchmark, the AMD Instinct MI300A APU was tested against the AMD Instinct MI210, NVIDIA A100 80 GB and NVIDIA H100 (80 GB) GPU. The AMD GPUs were running on the ROCm 6.0 stack & the NVIDIA GPUs were running on the CUDA 12.2.2 stack. The benchmark was configured to run for 20 time steps with the average time of execution per time step (seconds) taken as the figure of merit (FOM). All three configurations besides the Instinct MI300A were using a discrete CPU so a socketed CPU was configured with heterogeneous memory management to allow the GPUs to address the system