Deduplikáció

Deduplikáció, often translated as deduplication, is a process used in data storage and management to eliminate redundant copies of data. The primary goal of deduplication is to optimize storage space by ensuring that only one unique instance of a data block or file is stored. When identical data is encountered, subsequent occurrences are replaced with a pointer to the original stored instance. This technique can be applied at various levels, including file-level deduplication, block-level deduplication, and sometimes even byte-level deduplication.

Block-level deduplication is generally considered more effective as it can identify duplicate data segments within files, not just entire identical files. This is particularly beneficial for large files or files that change frequently, as only the modified blocks will be stored. The process typically involves hashing data chunks to create unique identifiers. These hashes are then compared against a database of existing hashes. If a match is found, the new data chunk is discarded and a reference is created.

The benefits of deduplication include significant storage cost savings, reduced network bandwidth usage for data transfer, and potentially faster backups and restores as less data needs to be processed. However, deduplication introduces some overhead. The process of hashing, comparing, and managing pointers requires processing power and memory. There can also be a slight increase in retrieval time as the system needs to reassemble data from original blocks and pointers. It is commonly implemented in backup systems, network-attached storage (NAS) devices, and enterprise storage solutions.