A Cross-Layered Readahead Architecture for Multi-Tiered Storage Systems

Recent researches have proposed multi-tiered storage systems that extend the storage hierarchy by using solid-state drives (SSDs) to cache data from the hard disk drives (HDDs). However, the current Linux readahead architecture fails to fully support the multi-tiered storage systems. To address this issue, we propose a new Linux readahead architecture. To make prefetching decisions, the framework analyzes not only the degree of data access sequentiality, but also the performance model of the destined storage device and the access regularities of the I/O workload on the corresponding storage device.