公开(公告)号：US10379954B2

公开(公告)日：2019-08-13

申请号：US14980248

申请日：2015-12-28

Applicant: TSINGHUA UNIVERSITY

Inventor： Jiwu Shu ,  Youyou Lu

IPC: G06F11/00 ,  G06F11/14 ,  G06F12/02

Abstract: The present invention provides a method and an apparatus for cache management of transaction processing in persistent memory. The method includes: when a transaction starts, reading old version data from non-volatile memory to a processor cache, and executing the transaction; during the execution of the transaction, allocating a space to generated new version data, and using a steal write-back technology to allow persistence of uncommitted data; when the transaction is committed or aborted, implementing forced persistence of transaction data to the non-volatile memory: after persistence of the transaction data or state is implemented to the non-volatile memory, writing the transaction data back to original data addresses, and using a no-force write-back technology to relax persistence of committed data to the non-volatile memory, where the transaction processing module periodically implements persistence of cached data to the non-volatile memory using bulk persistence; and when a system failure occurs, performing failure recovery processing on the transaction data. The method can reduce frequencies of data replication and data persistence in persistent memory.

公开(公告)号：US20170147208A1

公开(公告)日：2017-05-25

申请号：US14980462

申请日：2015-12-28

Applicant: TSINGHUA UNIVERSITY

Inventor： Jiwu Shu ,  Jiaxin Ou ,  Youyou Lu

IPC: G06F3/06 ,  G06F17/30

CPC classification number: G06F3/061 ,  G06F3/0659 ,  G06F3/0679 ,  G06F17/3007 ,  G06F17/30168 ,  G06F17/30218

Abstract: The present invention provides a method for constructing an NVRAM-based efficient file system, including the following steps: S1. determining a file operation type of the file system, where the file operation type includes a file read operation, a non-persistent file write operation, and a persistent file write operation; and S2. if the file operation type is a non-persistent file write operation, writing, by the file system, content of the non-persistent file write operation to a dynamic random access memory DRAM, updating a corresponding DRAM cache block index, and flushing, at a preset time point, the content of the non-persistent file write operation back to a non-volatile random access memory NVRAM asynchronously, or otherwise, copying, by the file system, related data directly between the NVRAM/DRAM and the user buffer. The method of the present invention can not only avoid additional copies and overheads of conventional software layers, but also improve write performance of the NVRAM file system by fully utilizing a characteristic of high write performance of the DRAM, thereby improving overall performance of the system.

公开(公告)号：US20170024324A1

公开(公告)日：2017-01-26

申请号：US14980346

申请日：2015-12-28

Applicant: TSINGHUA UNIVERSITY

Inventor： Jiwu Shu ,  Youyou Lu ,  Fei Li

IPC: G06F12/10 ,  G06F3/06

CPC classification number: G06F12/1009 ,  G06F3/0604 ,  G06F3/0631 ,  G06F3/064 ,  G06F3/0679 ,  G06F9/467 ,  G06F11/00 ,  G06F12/0246 ,  G06F2212/1016 ,  G06F2212/7201 ,  G06F2212/7207

Abstract: The present invention discloses a method for distributed transaction processing in a flash memory, including the following steps: S1. performing two-phase commit on a transaction, removing a state log record of a two-phase commit protocol, and internalizing as an operation on flash memory metadata in a transaction interface; S2. storing a temporary data object as a shadow version while performing the transaction, using a shadow mapping table to store the address of the shadow version or a state of a page, using page metadata to record transaction information, using a transaction metadata page to record a transaction state, and using a transaction state table to record an address of the transaction metadata page; and S3. when the coordinator or a participant fails, recovering the FTL mapping table, shadow mapping table, and transaction state table with the help of stored data and flash memory metadata. The present invention has the following advantages: the number of logs is reduced, and performance of transaction processing in a distributed flash memory environment is improved.

Abstract translation: 本发明公开了一种闪存中分布式事务处理的方法，包括以下步骤：S1。 对事务执行两阶段提交，删除两阶段提交协议的状态日志记录，并将其作为对事务接口中闪存元数据的操作进行内部化; S2。 在执行事务时将临时数据对象存储为阴影版本，使用阴影映射表来存储阴影版本的地址或页面的状态，使用页面元数据来记录事务信息，使用事务元数据页来记录 交易状态，并使用事务状态表来记录事务元数据页面的地址; 和S3。 当协调者或参与者失败时，借助存储的数据和闪存元数据恢复FTL映射表，阴影映射表和事务状态表。 本发明具有以下优点：减少了日志数量，提高了分布式闪存环境中的事务处理性能。