A Method for Retrieval and Storage of Flash Data Based on Binary Search of Unknown Length

Abstract

The invention discloses a method for retrieving and storing flash memory data on the basis of unknown length binary search, and belongs to the technical field of flash memory. By combining algorithms and ideas about the unknown length binary search, bitmap, load factor, erasing distance and the like, full address space (full address of a sector) binary search is replaced by the unknown length binary search, actual deletion is replaced by the bitmap, and full address space memory is replaced by the load factor and the erasing distance. The method for retrieving and storing the flash memory data improves performances of basis operation like inquiring, deleting and erasing of flash memory medium, simultaneously has the advantages of strong expandability and low occupancy of resources, and is easy to realize in a single chip machine of an embedded system or a non-operation system.

Description

technical field [0001] The invention relates to a method for retrieving and storing flash memory data based on binary search of unknown length, and belongs to the technical field of flash memory storage. Background technique [0002] Flash memory (FlashMemory) is a long-life non-volatile (it can still maintain the stored data information in the case of power failure) memory, data deletion is not in the unit of a single byte but in a fixed block The block size is generally 256KB to 20MB. Flash memory is a variant of electronically erasable read-only memory (EEPROM). The difference between flash memory and EEPROM is that it can be deleted and rewritten at the byte level instead of erasing the entire chip, so that flash memory can be updated faster than EEPROM . Because it can still save data when it is powered off, flash memory is usually used to save setting information, such as saving data in the BIOS (basic input and output program) of a computer, PDA (personal digital as...

AI Technical Summary

Problems solved by technology

[0010] Aiming at the deficiencies of the prior art, the present invention proposes a method for retrieving and storing flash memory data based on binary search of unknown length, which is an efficient method for storing and retrieving variable data in flash media based on bitmap and binary search of unknown length. To solve the problem that storage efficiency and retrieval efficiency cannot be balanced when existing flash media stores and retrieves volatile data

The present invention uses a bitmap to mark the validity of data, and then realizes efficient deletion operations; uses a load factor to determine the load percentage of each sector, and then solves the problem of slow storage speed caused by storing data in a sorted manner; uses unknown length binary Find, solve the efficient data retrieval in the ordered sequence of unknown length; use the erasing distance to solve the problem of extremely inefficient data movement caused by a full sector when storing data across sectors

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