Industry-University Cooperation Foundation Hanyang University

Ulsan National Institute of Science and Technology

Unist-Academy Industry Research Corporation

You Jip Won

Sung Roh Yoon

Jong Moo Choi

Soo Yong Kang

Jae Hyuk Cha

Beom Seok Nam

Sang Yup Lee

Dong Wook Kim

Sung Min Park

Jong Hwa Kim

Ik Joon Son

Tae Hwa Lee

Ho Young Jung

Provided is a database journaling method and apparatus for storing a log file in a storing apparatus by performing a lesser number of record commands to decrease a volume of data to be input and output by the storing apparatus, and the database journaling method may include determining whether a database is changed based on an operation performed on data in the database, generating a log file including log entries for the database when the database is changed, and performing journaling on the database by storing the generated log file in a storing apparatus, wherein each of the log entries includes a log record in which the data associated with a change of the database is stored, and metadata for the log record is recorded in a predetermined area embedded in the log record.

Database journaling method and apparatus

A data storing method performed by a data storing apparatus according to an exemplary embodiment of the present invention includes a step of calling insert operation for storing first data in a first page having a space for storing data, a step of checking whether overflow in which there is no space for storing the first data in the first page occurs, a step of checking whether the overflow occurs in the first page and dead data is stored in the first page, and a step of generating an overflow buffer page to store the first data in the overflow buffer page when the overflow occurs in the first page and the dead data is stored in the first page and there is a transaction accessing the dead data.

Data storing method using multi-version based data structure

The present invention relates to an apparatus and method for indicating flash memory life. While data is being stored in a flash memory, the number of writes in a plurality of blocks of the flash memory increases. The amount of flash memory life is calculated on the basis of the number of write times in the plurality of blocks. The calculated amount of life can be transmitted to a host. In addition, when the calculated amount of life is greater than a threshold value, a signal providing notice that the life of the flash memory has reached a dangerous level can be output.

Apparatus and method for indicating flash memory life

The present invention relates to a grouping method and device for enhancing redundancy removing performance for a storage unit such as a hard disk, a solid state disk (SSD), etc. The grouping method for enhancing performance of a redundancy removing technology may include: extracting samples from data that is stored in a buffer of a memory and is standing by to be processed; performing remaining calculations on the extracted samples; and grouping samples by connecting them to a bucket corresponding to a resultant value of the remaining calculations.

Grouping method and device for enhancing redundancy removing performance for storage unit

The present invention relates to a storage device that uses a flash memory that performs power loss recovery, and to a method of power loss recovery by using the storage device using the flash memory. The storage device stores change information on metadata in physical pages in which one or more logical pages are compressed and stored. The change information on the metadata is information representing how the metadata is changed in association with data in the one or more logical pages. The storage device may synchronize the metadata in the flash memory and recover the metadata by applying the change information on the metadata to the synchronized metadata when a power supply is disrupted.

Method and apparatus for power loss recovery in a flash memory-based SSD

The present invention relates to a method and device for storing data in a flash memory using address mapping for supporting various block sizes. A storage device determines the size of a block that a host system uses on the basis of the size of data that the host system requests and uses the determined block size as a mapping unit. Additionally, the storage device divides a logical address space into at least one area, and maps an address using the minimum units of different mappings in each divided area.

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Gyeonggi-do, South Korea

You Jip Won