Innodisk SATADOM-SH 3SE Series, Руководство пользователя

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SATADOM-SH 3SE
13 Rev 1.3 TPS, Jan., 2015
3.3 Error Detection and Correction
Highly sophisticated Error Correction Code algorithms are implemented. The ECC unit consists of
the Parity Unit (parity-byte generation) and the Syndrome Unit (syndrome-byte computation).
This unit implements an algorithm that can correct 40 bits per 1024 bytes in an ECC block.
Code-byte generation during write operations, as well as error detection during read operation, is
implemented on the fly without any speed penalties.
3.4 Wear-Leveling
Flash memory can be erased within a limited number of times. This number is called the erase
cycle limit or write endurance limit and is defined by the flash array vendor. The erase cycle
limit applies to each individual erase block in the flash device.
Innodisk SATADOM-SH 3SE uses a static wear-leveling algorithm to ensure that consecutive writes
of a specific sector are not written physically to the same page/block in the flash. This spreads
flash media usage evenly across all pages, thereby extending flash lifetime.
3.5 Bad Blocks Management
Bad Blocks are blocks that contain one or more invalid bits whose reliability are not guaranteed.
The Bad Blocks may be presented while the SSD is shipped, or may develop during the life time of
the SSD. When the Bad Blocks is detected, it will be flagged, and not be used anymore. The SSD
implement Bad Blocks management, Bad Blocks replacement, Error Correct Code to avoid data
error occurred. The functions will be enabled automatically to transfer data from Bad Blocks to
spare blocks, and correct error bit.
3.6 Power Cycling
Innodisk’s power cycling management is a comprehensive data protection mechanism that
functions before and after a sudden power outage to SSD. Low-power detection terminates data
writing before an abnormal power-off, while table-remapping after power-on deletes corrupt data
and maintains data integrity. Innodisk’s power cycling provides effective power cycling
management, preventing data stored in flash from degrading with use.
3.7 Garbage Collection
Garbage collection is used to maintain data consistency and perform continual data cleansing on
SSDs. It runs as a background process, freeing up valuable controller resources while sorting good
data into available blocks, and deleting bad blocks. It also significantly reduces write operations to
the drive, thereby increasing the SSD’s speed and lifespan.