In-Memory Search With Phase Change Device-Based Ternary Content Addressable Memory

Here, we proposed an in-memory search prototype based on phase change memory (PCM). First, using the PCM, a highly compact (8F ² ) and low-energy (0.3 fJ/bit/search) nonvolatile ternary addressable memory (TCAM) is demonstrated and achieved a $6.6\times $ energy saving and $50\times $ cell area saving over the 16T SRAM-TCAM. Thanks to the non-volatility and massive parallelism of the PCM TCAM to computing Hamming distance, the frequent memory access is alleviated, enabling search operation in situ. The prototype shows a high throughput of 256 GB/s in data deduplication application, obtaining more than $250\times $ energy saving and $42\times $ improvement in throughput over CPU. Our study provides a low-area-overhead, low-energy, and high-throughput solution for the storage system to perform search in situ.