NVM Compression—Hybrid Flash-Aware Application Level Compression

This paper describes NVM Compression, a novel hybrid technique that combines application level compression with flash awareness for optimal performance and storage efficiency. Utilizing new interface primitives exported by Flash Translation Layers (FTLs), we leverage the garbage collection available in flash devices to optimize the capacity management required by compression systems. We implement NVM Compression in the popular open source database MariaDB based on Oracle MySQL^TM and use variants of commonly available POSIX file system interfaces to provide the extended FTL capabilities to the user space application. The experimental results show that the hybrid approach of NVM Compression can improve compression performance by 2-3x, deliver compression performance for flash devices that is within 5% of uncompressed performance (and sometimes exceed uncompressed performance due to less data writes), improve storage efficiency by 19% compared to legacy Row compression method, reduce data writes by up to 4x when combined with other flash aware techniques such as Atomic Writes, and deliver further advantages in power efficiency and CPU utilization.