Method for writing transaction on basis of de-duplication SSD (solid state disks)

Abstract

The invention discloses a method for writing transaction on the basis of de-duplication SSD (solid state disks). The method includes transaction read and write requests, request submission, request aborting and transaction recovery processes. Transaction write requests include computing fingerprints according to to-be-written data, searching fingerprint databases or transaction tables, directly updating the transaction tables if targets are hit, allocating new physical pages if the targets are not hit, writing the data and updating the transaction tables; transaction read requests include searching the transaction tables or address mapping tables according to logic addresses to obtain corresponding physical addresses, returning data read at the physical addresses if targets are hit, returning error information if the targets are not hit; request submission includes updating table items in the transaction tables, and updating the address mapping tables, inverse mapping tables and the fingerprint databases according to the transaction tables; request aborting includes marking the new physical pages allocated to the aborted transaction as junk pages; the transaction recovery processesinclude reconstructing information of the address mapping tables and the like according to transaction tables stored in flash after system breakdown. The method has the advantages that transaction processing mechanisms can be implemented in the de-duplication SSD, and the data consistency can be guaranteed.

Description

technical field [0001] The invention belongs to the field of SSD (Solid State Disk, solid state disk, solid state disk for short) storage control, and more specifically relates to a transaction writing method based on deduplication SSD. Background technique [0002] For performance, lifetime and cost considerations, many SSD products have adopted data deduplication technology to reduce the data actually written into the flash chip. Data deduplication technology, also known as data deduplication, means that in a data file collection, only unique data units are saved, while duplicate data is deleted. Deduplication technology can improve the performance, lifespan and cost of SSD, but it also brings more data consistency problems. [0003] For ordinary SSDs that do not use deduplication technology, there are already some transaction-based solutions that provide data consistency guarantees. On the one hand, these solutions can ensure data consistency when accessing SSDs through...

AI Technical Summary

Problems solved by technology

A new type of storage device that adopts the ring commit protocol - transactional flash memory (Transactional Flash, namely TxFlash), lightweight transactional SSD that supports different isolation levels between transactions (namely LightTx), transaction for embedded database software SQLite The permanent flash translation layer (X-FTL) and others have proposed transaction processing mechanisms for ensuring the data consistency of ordinary SSDs, but none of these transaction processing mechanisms can be applied to deduplication SSDs to meet the transaction processing requirements of deduplication SSDs.

Images