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Topic:
Action-Reaction: Solid State Disk VS Hard Disk Drive
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jdawe
Posts:
318
Registered:
11/8/09
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Action-Reaction: Solid State Disk VS Hard Disk Drive
Posted:
May 15, 2013 5:47 AM
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SSD - HDD
A Solid State Drive (SSD) is probably better known as a Centre State Drive, that is the data is all stored in the centre rather than the perimeter like a Hard Disk Drive (HDD) does on curved disks that rotate around the centre.
Centre - Perimeter
Linear - Curvature
Imagine taking a ballpoint pen and placing the point on the centre of a spinning disc. Imagine this is the read head of a SSD. This head doesn't have to move anywhere to access the data stored because all the data is stored in the same spot ? directly in the centre. Because the head doesn't have to move to access the data it is has theoretically instantaneous access.
Static - Variable
Instantaneous - Gradual
The problem here is that only one unit of data can be stored in the centre. So to increase capacity we have to place another disk over the top of the first one. This will give us two units of storage space.
I suppose you could imagine a plate full of 10 pancakes stacked up then taking a pen and driving it through the centre of the stack from top to bottom. Each pancake layer has a centre with the pen going through it. Each layer of pancake has one centre that can only store one unit of data so in a stack of 10 pancakes you can store 10 units.
So, a SSD is going to store data in a vertical straight line from down to up rather than a hard drive that stores data horizontal from right to left along a curved disk.
Vertical - Horizontal
This is important to understand because a HDD storing data horizontally from right to left is going to wear 'inward' so the more times it is used the more it wears 'in' and the better performing it will be. In direct opposition the SSD storing data vertically from down to up is going to wear 'outward' so the more times it is used the more it will wear out and the less performing it will be.
If we look back at the plate stacked up with pancakes and a single pen driven vertically through the centre the pancakes represent 'quantity' and that discrete quantity opposes the single pen continuum.
Singular - Plural
Continuum - Discrete
No matter how many pancakes we add to the plate there will only ever be a single continuous tunnel down the middle.
Absolute - Relative
The pancakes revolve relative to the centre that is in a fixed state.
You don't need to worry about the pancakes touching each other because when disks spin up they 'float' and are independent of the other discs.
The disks horizontally levitate opposed to the centre tunnel which represent vertical gravitation.
Vertical - Horizontal
Gravitation - Levitation
Linear - Curvature
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This newsgroup post is an edited transcript of a number of posts I made to an Internet forum where a question was raised regarding the operation of an Solid State Drive.
http://forums.whirlpool.net.au/forum-replies.cfm?t=2097941#r13
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