Out-of-core diffraction algorithm using multiple SSDs for ultra-high-resolution hologram generation

The diffraction calculation is critical in computer-generated holography (CGH). However, it becomes a performance bottleneck when generating ultra-high-resolution holograms due to limited physical memory space. We propose a novel out-of-core (OOC) diffraction algorithm that utilizes multiple solid-state drives (SSDs) to address this issue. Our method employs the implicit diffraction approach and exploits its even-odd separation characteristic to utilize multiple SSDs optimally. We implement our algorithm on two machines, each with four SSDs, and compare it with prior OOC diffraction methods and a RAID-based solution. Our approach achieves up to 2.43 times higher performance than prior OOC methods for large-scale diffraction calculations, with continued performance improvement observed by adding more SSDs. Additionally, our method reduces the generation time for ultra-high-resolution holograms (200K x 200K) by 38% compared to the prior OOC method with multiple SSDs. These results demonstrate the effectiveness of our algorithm for extreme-scale CGH.