Date of Award

Fall 12-20-2020

Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Science (MS)


Computer Engineering


Yifeng Zhu

Second Committee Member

Vincent Weaver

Third Committee Member

Bruce Segee


As the non-volatile memory (NVM) technology offers near-DRAM performance and near-disk capacity, NVM has emerged as a new storage class. Conventional file systems, designed for hard disk drives or solid-state drives, need to be re-examined or even re-designed for NVM storage. For example, new file systems such as NOVA, HMFS, HMVFS and Ext4-DAX, have been developed and implemented to fully leverage NVM’s characteristics, such as fast fine-grained access. This thesis research uses a variety of I/O workloads to evaluate the performance overhead of the TLB (translation lookaside buffer) in various file systems on emulated NVM storage systems, in which NVM resides on the memory bus. As NVM’s capacity becomes much greater than DRAM and applications’ footprints continue to increase rapidly, the number of TLB entries scales up with the same pace, leading to a significant amount of TLB misses. The goal of this research is to gain insights into file system optimizations on storage-class memory. Experimental results show that NVM based file systems can have 50% more TLB overhead compare to with conventional file systems, under the same file operations. Profiling based on performance counters show that TLB-friendly journaling/logging should be taken into consideration into future file system design.