Datasheet

IBM eXFlash DDR3 Storage DIMMs 3
IBM eXFlash DIMMs have the following key characteristics:
Industry standard LP DIMM form factor supports standard DDR3 memory DIMM slots on selected
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System x servers.
Uses cost-effective 19 nm MLC NAND technology with FlashGuard technology for high read and write
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performance to fulfill client needs in the enterprise space.
High endurance, with up to 10 drive writes per day (DWPD) during a 5-year lifecycle to withstand
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applications with intensive read/write workloads.
Up to 12.8 TB total flash memory-channel storage capacity per server.
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Support of up to 1600 MHz DDR memory speeds and the usage of available DDR3 memory channels.
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Support for intermixing with standard registered memory DIMMs (RDIMMs) on the same memory
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channel.
FlashGuard technology extends the native endurance of commercial-grade MLC flash memory by
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using the following features:
Aggregated Flash Management
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Advanced Signal Processing
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Enhanced Error Correction
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DataGuard technology protects against data corruption and loss by using the following features:
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Full data path protection
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Flexible Redundant Array of Memory Elements (F.R.A.M.E.) data recovery algorithm
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EverGuard technology protects data in the event of unplanned power outages.
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Solid-state storage has a huge but finite number of program/erase (P/E) cycles, which affects how long it
can perform write operations and thus its life expectancy. Solid-state device write endurance is typically
measured by the number of program/erase cycles that the device can incur over its lifetime, which is
listed as Total Bytes Written (TBW) or Drive Writes Per Day (DWPD) in the device specification.
The TBW value that is assigned to a solid-state device is the total bytes of written data that a drive can be
guaranteed to complete. Reaching this limit does not cause the drive to immediately fail; the TBW simply
denotes the maximum number of writes that can be guaranteed. A solid-state device does not fail upon
reaching the specified TBW, but at some point after surpassing the TBW value (and based on
manufacturing variance margins), the drive reaches the end-of-life point, at which time the drive will go
into read-only mode. Because of such behavior, careful planning must be done when you use SSDs in
application environments to ensure that the TBW of the drive is not exceeded before the required life
expectancy is reached.