| Since the 1990’s,distributed storage system emerged in storage industry has been gradually applied in various critical fields,while the data security and performance of the system has also been challenged.Most of distributed storage systems have to maintain their performance at the price of the data’s reliability by introducing data cache technology,such compromise put the distributed storage system in the dilemma of being challenged by the risk of date security and repair performance of data consistency.Storage systems introduced various techniques to reduce the risk of losing their cache data.Disk array storage systems usually use their batteries to protect data storage in their memory,likewise,some distributed storage systems use memory protected by batteries to protect data.For the purpose of reducing the impact of a single node outage,most distributed storage systems apply cache back-up technology which can backup cached data to multiple nodes at the same time.With the development of technology,the NVDIMM(non volaitle dual inline memory module)which can ensure data’s transferring from memory to flash memory has gradually matured.Intel’s most recent CPU has been equipped with NVDIMM as its standard support equipment.This study intends to apply NVDIMM,the technology which can protect cache date for the entire storage system when the power is off,to improve data security and performance of the distributed storage system.To this end,this thesis proposes a method about how to use and manage NVDIMM,which will protect cache data comprehensively in the distributed storage system,as well as a distributed logging strategy based on NVDIMM to maintain the consistency of data stored in various nodes when power failure occurs.Moreover,in view of the fact that a distributed storage system needs more time to recover its massive data,this thesis also designed a comprehensive repairing strategy based on the data consistency of NVDIMM,which will repair massive small file data immediately once the power is restored.To sum up,we can build a complete cache data protection scheme for distributed storage system using NVDIMM.Author of this thesis has proved NVDIMM’s protection effects on cache data by actual test.Such effects include improving data protection,quickening data reading and writing,and enhancing data consistency repair.According to actual test,distributed storage system equipped with NVDIMM can protect data when power failure occurs,meanwhile,data writing bandwidth has been increased 34.11%,responding time for writing has been reduced 25.75%,and speed of repairing massive small file has been increased by 20 times. |
