Improving Path Lookup and File Access of NVMM-Based File Systems with PIM

Abstract

With the emergence of non-volatile memories with fast access performance byte addressability and non-volatility characteristics the line between main memory and storage is gradually broken This means that we can use non-volatile memories as main memory and such main memory can also be used as storage At the same time researchers have begun to notice that traditional file systems are designed for disk If such file systems are used on non-volatile memories the performance of the system will be affected by the software overhead Therefore there are many file systems based on non-volatile main memory that have been proposed to solve this problem However we found that the file system based on non-volatile main memory has irregular memory access when doing path lookup In addition if the file size to be accessed exceeds the least level cache there will be frequent cache misses These problems cause the system to access the memory through the external memory channel which will make the system less efficient and increase system power consumption In order to solve this problem we have proposed PHSIM In PHSIM we handle path lookup and file access through process-in-memory technology so that we can take advantage of the internal memory channel to reduce the delay and energy consumption caused by accessing memory The experimental results show that on all the workloads PHSIM can improve 41% performance and decrease 40% energy consumption on average

Date of Award	2019
Original language	English
Supervisor	Da-Wei Chang (Supervisor)