Hatteland HD 12T21 MMC Series, User Manual

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SSD Selection Guide
Appendix
IND100077-130
Calculation of required size of SSD (Multi-Level Cell - MLC) device)
The table below details the write endurance of the an enterprise environment. All values are verified by Hatteland
Display during the qualification / selection process.
Write Endurance Specifications
Intel® SSD 320 Series
Write Endurance Specifications
Current 2.5” SSD (MLC)
Device Size Value in TBW (Terabytes) Device Size Value in TBW (Terabytes)
40 GB 5 80 GB 45
80 GB 10 120 GB 70
120 GB 15 160 GB 100
160 GB 15 240 GB 140
300 GB 30 300 GB 225
600 GB 60 600 GB 330
Write endurance is measured while running 100%
random 4KB (4096 bytes) writes spanning 100% of
the drive using Iometer.
JESD218 standard1 and based on JESD219 workload.
Formula for calculating disk size:
z
=
y
*
x
Where
y
= Requested minimum lifetime (with respect to wear out, [year]).
Where
x
= Data rate (GB /per year).
Where
z
= Total amount of data written data to SSD during its whole lifetime.
Step-by-Step Calculation
Step 1: Measure (preferred) or estimate data rate y , [GB /per year].
Step 2: Define minimum expected lifetime for SSD device x [year].
Step 3: Calculate total amount of data written to the SSD during its whole lifetime, z = y * x .
Step 4: Use table, column 2 , the z value shall be less or equal to the value in the table to achieve requested lifetime.
Write Endurance Specifications
Intel® SSD 320 Series
Write Endurance Specifications
Current 2.5” SSD (MLC)
Device Size Value in TBW (Terabytes) Device Size Value in TBW (Terabytes)
40 GB 5 80 GB 45
80 GB 10 120 GB 70
120 GB 15 160 GB 100
160 GB 15 240 GB 140
300 GB 30 300 GB 225
600 GB 60 600 GB 330
Step 5: Select the SSD device,
column 1 ,
which corresponds to the selected value in
column 2
.
Step 6. Check that the size of the selected SSD is greater than required size of the SSD, if not select the size of the
SSD that match customer requirements.
Released