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    Dan's Tech Tips:
Should You Defrag Solid-State Drives?
Article Source: Kim Komando's tip of the day 3/18/2011
No, defragmenting solid-state drives isn't necessary. In fact, it's not a good 
idea at all. Read on to find out why.
Let's refresh our memories about how hard drives work. That will help you 
understand why SSDs follow different rules. We'll start by talking about the 
traditional hard drive.
A traditional hard drive uses magnetism to store information. Inside each drive 
is one or more "platters." These platters are metal disks that spin rapidly. 
The standard speed for desktop hard drive platters is 7,200 RPM.
Each platter contains billions of microscopic magnetic regions. These regions 
can be either magnetized or de-magnetized. The computer reads those as binary 
ones and zeros, respectively. Strings of ones and zeros are how all computer 
information is stored.
A magnetic head reads and writes information on each platter. The head is 
mounted on a swinging arm. It has to physically move across the platter to find 
information.
It's actually the same idea as a turntable record player. The magnetic head is 
like the record needle. The difference is that the hard drive head hovers over 
the platter. When the head touches the platter, you have a serious problem.
This approach has worked for decades, but it has some drawbacks. One major 
problem is reliability. There are a lot of moving components that can fail.
And when they fail, your information is often severely damaged. That is why 
having a backup system is essential.
Another problem is speed; the components can only move so fast. This limits how 
quickly information can be written and read. Some drives spin the platters at 
10,000 RPM or higher. That increases data transfer, but it also wears the drive 
out faster.
The moving parts are also a problem as hard drive storage gets bigger. There is 
more information on the drive to search. Finding the right file can take longer.
That leads us to the most common problem, which is fragmentation. Fragmentation 
occurs on every computer during normal use. Files are constantly being moved, 
written, changed, deleted and overwritten.
You often end up with one program file in one spot. And a related program file 
will be in a completely different spot. You might even have one file broken up 
into several locations.
What happens when the computer accesses that program or file? It has to visit 
several spots on the platter to assemble it for you. And that takes extra time. 
Your computer slows down.
You can visualize it this way. Imagine listening to a vinyl record where every 
song is broken into segments. And those segments are scattered around the 
record.
Listening to a song would be annoying. The needle would have to lift and move 
to each new segment. That means the song would keep pausing. And listening to a 
complete song would take forever.
That is why defragmentation programs exist. These move related information back 
together on the platter. This means the head doesn't have to move so much. It 
helps your computer run smoother.
Now let's talk about how solid-state drives work. These have been around for 
years. But until recently, they were way too expensive for most consumers.
They are still more expensive than traditional hard drives. But prices are 
falling rapidly, and SSD storage size is increasing. In fact, SSDs are the only 
option on some laptops now. The MacBook Air is a good example.
SSDs are built around flash memory. That's the same technology used for thumb 
drives and memory cards. Most media players, tablets and smart phones use flash 
memory as well.
Flash memory is made up of cells. There are a few different kinds of these 
cells. But we don't need to worry about that for the moment.
The upside is that there are no moving parts, hence the "solid state" moniker. 
Everything is read and written electronically. That increases both reliability 
and speed.
It also makes fragmentation a moot point. It doesn't matter where files are 
located on the SSD. There are no moving parts to slow things down. Reading 
files from multiple locations takes no extra time.
In fact, defragmenting an SSD is actually not good for it. That's because flash 
memory has a major drawback: It wears out over time.
Flash memory is made up of billions of cells. Writing information changes the 
contents of the cell. Unfortunately, each cell can only be changed so many 
times. After that, it won't change anymore. Eventually, your SSD loses all its 
storage space.
Flash cell lifecycle is being steadily improved. A modern, SSD from a reputable 
manufacturer should last at least 5 years. Much of that is thanks to 
wear-leveling controllers.
These controllers monitor how often each cell is used. They make sure data is 
spread evenly throughout the drive. This keeps cells from being worn out too 
quickly.
Manufacturers are also over-provisioning. This is putting more memory in the 
drive than is listed. If some cells fail prematurely, they can be ignored with 
minimal impact.
Defragmenting a drive moves a lot of data around. This means you are changing a 
lot of cells at once. And that means you are wearing the SSD out more quickly.
Of course, the impact is slight overall. It would take a lot of defragmenting 
to wear out the drive. But, again, it doesn't actually help performance.
If you want to get an SSD, make sure you have Windows 7. It is designed to work 
properly with SSDs. Earlier Windows versions will treat the SSD like a regular 
hard drive. This means you won't get many of the benefits.
Also, remember that SSDs are still largely new to the consumer market. You will 
probably encounter poor products and manufacturing errors. Having your 
sensitive information backed up is still very important.
Below are some sites to review and compare solid state drive 
cost/size/performance:
1. Solid State Hard Drive - Hard Drives - Compare Prices, Reviews and Buy at 
Nextag - Price - Review:
http://www.nextag.com/solid-state-hard-drive/products-html
2. Solid State Drive Comparison Round 2, Techspot Review:
http://www.techspot.com/review/181-solid-state-drive-roundup2/
3. Solid State Review, Top Ten Reviews for 2012:
http://solid-state-drive-review.toptenreviews.com/
4. Review: Hard disk vs. solid-state drive -- is an SSD worth the money ...
http://www.computerworld.com/s/article/9134468/Review_Hard_disk_vs._solid_state_drive_is_an_SSD_worth_the_money_
5. SSD Vs HDD Performance Speed Life Cost Power Reliability
http://www.teknocrat.com/ssd-vs-hdd-analysis-and-comparison.html
If you have any questions about the tips posted in Dan's Tech tips, please 
contact Dan at the following email address:
dthompson5@xxxxxxxxx

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