Datasheet

IBM United States Hardware Announcement 114-135 IBM is a registered trademark of International Business Machines Corporation
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give an estimate of the drive's remaining life based on the workload to which the
drive will be subjected. The TBW value assigned to a solid-state drive is the total
bytes of written data (based on number of P/E cycles) a drive can be guaranteed to
complete. Reaching this limit does not cause the drive to immediately fail; it simply
denotes the maximum number of writes that can be guaranteed.
A solid-state drive will not fail upon reaching the specified TBW. At some point based
on manufacturing variance margin, after surpassing the TBW value, the drive will
reach the end-of-life point, at which the drive will go into a read-only mode.
As a result of the technology limitations, care must be taken to use SSDs in
environments that will not exceed the TBW of the drive prior to the required life
expectancy of the application.
As an example, assume an access pattern of 50% random data and 50% sequential
data with block size mixes of 5% of the data is 4k block size, 5% of the data is 8k
block size, 10% of the data is 16k block size, 35% of the data is 64k block size, and
35% of the data is 128k block size. For a drive capable of 72 TB of lifetime writes,
assuming an approximation of the workload stated above as being worst case, the
drive workload must be limited to no more than 40 GB of writes per day to last five
years and stay inside the 72 TBW limit. For the device to last threes years, the drive
write workload must be limited to no more than 65 GB of writes per day.
Additional information is available at
http://www-03.ibm.com/systems/x/options/storage/solidstate/index.html
IBM's warranty for the device is limited to drives that have not reached the
maximum guaranteed number of program/erase cycles, as stated below. A drive
that reaches this limit may fail to operate according to its specifications.
Maximum warranted drive writes per drive is 0.38 Full Drive Writes per Day for 5
years or 165 TB TBW on the 240 GB SSD depending on workload and data patterns.
Maximum warranted drive writes per drive is 0.38 Full Drive Writes per Day for 5
years or 330TB TBW on the 480 GB SSD depending on workload and data patterns.
Maximum warranted drive writes per drive is 0.38 Full Drive Writes per Day for 5
years or 665 TB TBW on the 960 GB SSD depending on workload and data patterns.
User group requirements
This announcement satisfies or partially satisfies the requirements from one or
more of the worldwide user group communities. Groups include COMMON, COMMON
Europe, Guide Share Europe (GSE), InterAction (Australia/New Zealand), Japan
Guide Share (JGS), and SHARE Inc.
Planning information
Customer responsibilities
The new IBM SATA MLC Entry SSD products are designed as customer setup.
Customer installation instructions can be found in the Installation and User's Guide
for the system into which the drive is to be installed.
Cable orders
None
Installability
The IBM SATA SSDs require about 20 minutes for installation.
Installation includes unpacking, attaching a customer-provided line cord, setting up,
and powering on.