A redundant array of independent memory (RAIM) is a design feature found in certain

computer A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic set ...

s' main

random access memory Random-access memory (RAM; ) is a form of electronic computer memory that can be read and changed in any order, typically used to store working data and machine code. A random-access memory device allows data items to be read or written ...

. RAIM utilizes additional memory modules and striping

algorithms In mathematics and computer science, an algorithm () is a finite sequence of mathematically rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for per ...

to protect against the failure of any particular module and keep the memory system operating continuously. RAIM is similar in concept to a redundant array of independent disks (RAID), which protects against the failure of a disk drive, but in the case of memory it supports several DRAM device chipkills and entire memory channel failures. RAIM is much more robust than parity checking and

ECC memory Error correction code memory (ECC memory) is a type of computer data storage that uses an error correction code (ECC) to detect and correct ''n''-bit data corruption which occurs in memory. Typically, ECC memory maintains a memory system immun ...

technologies which cannot protect against many varieties of memory failures. On July 22, 2010,

IBM International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

introduced the first high end computer server featuring RAIM, the zEnterprise 196. Each z196 machine contains up to 3 TB (usable) of RAIM-protected main memory. In 2011 the business class model z114 was introduced also supporting RAIM. The formal announcement letter offered some additional information regarding the implementation:

References

{{Reflist, 2 Computer memory Error detection and correction Fault-tolerant computer systems

See also

References