For
computer memory
In computing, memory is a device or system that is used to store information for immediate use in a computer or related computer hardware and digital electronic devices. The term ''memory'' is often synonymous with the term '' primary storag ...
, Memory ProteXion, found in
IBM xSeries servers, is a form of "
redundant bit steering". This technology uses redundant bits in a
data packet
In telecommunications and computer networking, a network packet is a formatted unit of data carried by a packet-switched network. A packet consists of control information and user data; the latter is also known as the '' payload''. Control inform ...
to recover from a DIMM failure.
Memory ProteXion is different from normal ECC
error correction in that it uses only 6 bits for ECC, leaving 2 bits behind. These 2 bits can be used to re-route data from failed memory, much like
hot spare
A hot spare or warm spare or hot standby is used as a failover mechanism to provide reliability in system configurations. The hot spare is active and connected as part of a working system. When a key component fails, the hot spare is switched i ...
on a
RAID
Raid, RAID or Raids may refer to:
Attack
* Raid (military), a sudden attack behind the enemy's lines without the intention of holding ground
* Corporate raid, a type of hostile takeover in business
* Panty raid, a prankish raid by male college ...
. The ECC is used to reconstruct the data, and the extra bits to store it.
Memory ProteXion, also known as “redundant bit steering”, is the technology behind using redundant bits in a data packet to provide backup in the event of a DIMM failure. One failure does not cause a
predictive failure analysis Predictive Failure Analysis (PFA) refers to methods intended to predict imminent failure of systems or components (software or hardware), and potentially enable mechanisms to avoid or counteract failure issues, or recommend maintenance of systems pr ...
to be issued on the DIMM, but 2 failures and more will issue a PFA to inform the system administrator that a replacement is needed.
See also
*
Chipkill
External links
Memory ProteXion
Computer memory
Error detection and correction
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