Memory scrubbing, also known as data scrubbing and data cleansing, is an error correction technique. This background process periodically inspects the contents of memory, and fixes any errors or inconsistencies by replacing them with a functional copy of the data. A RAID controller, for instance, can scrub the data in its arrayed disks, checking for any defective blocks of data before allowing the data to be accessed.
Today’s chips, especially DRAM and SRAM, have a physical structure of the memory small enough to be affected by natural background radiation (e.g., cosmic rays and alpha particles). This radiation can change the contents of memory, and such inconsistencies are called “soft errors.” Scrubbing is an effective method of correcting such errors.
Data scrubbing is one method used in the programming of FPGAs (field-programmable gate arrays).
Data, File system, Memory, Memory terms
File systems that support data scrubbing include Btrfs and ZFS.
