December 28, 2011

EMC Symmetrix calculations for Heads, Tracks, Cylinders, GB

Here is the quick and dirty math on EMC Symmetrix Heads, Tracks, Cylinder sizes to actual usable GB’s of space.

Based on different generations of Symmetrix systems, here is how the conversions work.
Before we jump into each model type, lets look at what the basics are, with the following calculations..
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There are s number of splits (hyper) per physical device.
There are n number of cylinders per split (hyper)
There are 15 tracks per cylinder (heads)
There are either 64 or 128 blocks of 512 bytes per track
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All the calculations discussed here are for Open Systems (FBA) device types. Different device emulations like 3380K, 3390-1, 3390-2, 3390-3, 3390-4, 3390-27, 3390-54 have different bytes/track, different bytes/cylinder and cylinders/volume.
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Symmetrix 8000/DMX/DMX-2 Series
Enginuity Code: 5567, 5568, 5669, 5670, 5671
Includes EMC Symmetrix 8130, 8230, 8430, 8530, 8730, 8830, DMX1000, DMX2000, DMX3000 and various different configurations within those models.

GB = Cylinders * 15 * 64 * 512 / 1024 / 1024 / 1024

eg: 6140 Cylinder devices equates to 2.81 GB of usable data
6140 * 15 * 64 * 512 / 1024 / 1024 / 1024 = 2.81 GB


Cylinders = GB / 15 / 64 / 512 * 1024 * 1024 * 1024

Where
15 = tracks per cylinder
64 = blocks per track
512 = bytes per block
1024 = conversions of bytes to kb to mb to gb.
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Symmetrix DMX-3/DMX-4 Series
Enginuity Code: 5771, 5772, 5773

Includes EMC Symmetrix DMX-3, DMX-4 and various different configurations within those models.

GB = Cylinders * 15 * 128 * 512 / 1024 / 1024 / 1024

Eg: 65520 Cylinder device equates to 59.97 GB of usable data
65540 * 15 * 128 * 512 / 1024 / 1024 / 1024 = 59.97 GB


Cylinders = GB / 15 / 128 / 512 * 1024 * 1024 * 1024

15 = tracks per cylinder
128 = blocks per track
512 = bytes per block
1024 = conversions of bytes to kb to mb to gb
.
Symmetrix V-Max
Enginuity Code: 5874

Includes EMC Symmetrix V-Max and various different configurations within this model.

GB = Cylinders * 15 * 128 * 512 / 1024 / 1024 / 1024

Eg: 262668 Cylinder device equates to 240.47 GB of usable data
262668 * 15 * 128 * 512 / 1024 / 1024 / 1024 = 240.47 GB


Cylinders = GB / 15 / 128 / 512 * 1024 * 1024 * 1024

15 = tracks per cylinder
128 = blocks per track
512 = bytes per block
8 bytes = 520-512 used for T10-DIF
1024 = conversions of bytes to kb to mb to gb

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