Checkpointing a journal by virtualization of non-volatile random access memory

• Main Authors: Barszczak, Tomasz, Zuo, Xiaoshan
• Format: Patent
• Language: English
• Published: 10.07.2018
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; PHYSICS

Methods, systems, and computer programs are presented for virtualizing Non-Volatile Random Access Memory (NVRAM). A first area in RAM is labeled as active area and a second area as non-active area, and an active journal and a non-active journal are created in permanent storage. A transaction is created for each write made to the virtual NVRAM, and the created transactions are written to the active journal and to the active area. When the active journal is greater than a predetermined size or a timeout occurs, a checkpoint is created by copying contents from the active area to the non-active area, switching status of the active area and the non-active areas (the active area becomes the non-active area and the non-active area becomes the active area), switching status of the active journal and the non-active journal, and copying the content of the current non-active area to permanent storage.