detraging the hard drive on your gps

Then there's the other side of the coin ... some manufacturers recommend defragging their solid-state devices. So even the 'experts' don't agree as to the benefits of defragging solid-state devices.

But one thing most all solid-state manufacturers seem to agree on is whether defragging decreases the life of the solid-state device. Per Corsair's "Wear Leveling and Life Span" FAQ on their USB drives, their better flash drives are guaranteed for at least 100,000 writes per block (that's each section of the drive). These drives use "wear leveling". When referring to a 8GB drive, their data sheet says "one can write 210 GB of data to the drive each day, for ten years!". I don't think any defrag agenda will exceed this.

RT

May not hurt the GPS but it will certainly not help! Since Gps devices do not have a physical hard drive that would benefit from this. Although wearing out the flash memory should not be an issue unless you are doing defrags constantly. More of a possibility of something going wrong in the defrag process and rendering the GPS software inoperative.

If not broke, don't fix.

I really do not know, but I did a search and found this from a source I trust - Leo Notenboom

"You should never defragment a flash drive.
•
Files are stored on hard disks in pieces; frequently in 512 byte chunks. Now, there's no requirement that these chunks be next to, or even near each other. That means that a file could have its contents spread out in totally random places on the hard disk. You normally never see this, because the file system takes care of locating all those chunks when you read or write a file.

On a traditional hard disk there's a physical read/write head that moves around on the media when data is being accessed. Much like the laser in a CD player (or the needle on a record player), the disk spins underneath it, while the head moves in and out to locate the proper "track" that contains the next chunk of the file that's being accessed.

"The more you write to a flash device the shorter its lifespan will be."Moving that read/write head takes time.

So, if you can ensure that all the chunks of a file are next to each other or "contiguous", the head doesn't need to move as much, and reading the file is faster.

And that's what defragmenting, or "defragging", a hard disk is all about: rearranging where on the disk the file chunks are stored so that when the time comes to access a particular file, all the chunks are together and the read/write head doesn't need to move as much.

Flash drives have no read/write head.

In fact, flash drives have no moving parts at all. Everything that makes it look and act like a hard drive is actually done by mimicking the characteristics of a hard drive in the flash drive's circuitry.

Defragging a flash drive will get you no performance benefits. Since there's no head to move, there's no additional time cost in fetching one chunk of data from a flash drive over any other. It doesn't matter how the files are laid out, it's all just as fast.

So now that I've convinced you that there's no point in defragging a flash drive, why did I say that you should never do it?

Flash memory wears out.

Writing to flash memory causes it to degrade ever so slightly. (Reading does not.) The more you write to a flash device the shorter its lifespan will be.

Now, don't get me wrong, "normal" usage should be just fine. And the technology continues to improve almost daily. Not only is the underlying technology improving, but the techniques to mitigate the problem are improving as well. For example, most flash drives try to "spread out" write activity across the entire device, so that even if you're constantly re-writing the same data over and over again, the device will "move it around" so you're not wearing a single spot on the device faster than any other.

But still ... flash memory wears out.

If you're regularly defragging a flash drive, you're adding thousands upon thousands of write operations each time you do so. Whatever the expected lifespan of the device, you could easily be cutting it in half or worse.

For no benefit.

(Full disclosure: OK, a reader did comment on a prior article with a potential benefit - defragmented files are easier for recovery utilities to recover. Fair enough. In my opinion that's not even close to a good enough reason to shorten your flash drive's lifespan. Use a good backup strategy instead.)

So defrag your hard drives every so often. But never defrag your flash drives, there's just no point."

You are correct, I use to defrag my 660 and 680 until I was told not to do it since it was a solid state drive and I have not since defrag my 880 since I have received it.. as stated above, it is best not to as stated in previous messages.

Funny. I linked to this on page one.

**********************************************

Thanos, even though your post sort of agrees with mine, I find its tone insulting because it flat out states that those who are not in IT should be ignored. I'm not in IT. I've only been involved with computers since the TRS-80 and have kept up with current trends.

I've been in IT for almost 30 years, and in my opinion, flash drives can get fragmented.

Fragmentation comes as files are written to a drive and deleted. When files are deleted there is a gap left in the blocks that are written. If the operating System (Garmin in this case) tries to write a new file it will start at the open spot, and write until it fills up the location the old file was stored in. It then looks for the next location and continues writing until all of the file is written. repeated deletes and writes result in ever increasing fragments of files. So, yes, unless the Operating System is actively de-fragmenting the flash drive will become fragmented.

On non solid state drives the re-positioning or seek time is a significant part of the read operation. On a Solid State Drive such as a flash drive "seek time" not significant. Combine that with wear leveling programs on the drive, and the "limited" number of it probably is not recommended that you defrag a flash drive. There may be some small gains, but, it's not worth the added wear/

In my not so humble opinion...

beas

DO what is best for you!... What works for one, may or may not work for another.

"If it's NOT Broke then don't fix it has always been best for me!"

Alandb said in part..

I checked my Nuvi 1300WT GPS and it said.. "Defrag Count = 34". Now I can tell you right now that I've never "defraged" my unit myself.. so I can only assume, per some of the comments of others, that it does it on its own.

When it does it I have not the slightest idea.. but obviously it did it 34 times.

Nuvi1300WTGPS

Could you list "some manufacturers" who recommend doing defraggs? Could you site examples where I can go to look up these recommendations?

Thank you

I defragmented my GPS (Nuvi 1250t), but haven't noticed any difference in speed. I have to admit that even before defragmentation it was working very smooth. At the end of the process defragmentation program gave me a message that few (4) files were unmovable and the main map image (gmapprom.img) was to big, with unsufficient free space, to be moved.

I don't like to brag but I have been in IT for 46 years. I have seen every technical achievment for storage since 1966. SSD (Solid State Devices) have no moving parts. There is no need to defrag these devices. You are only wearing out the device quicker. Even Microsoft Windows 7 has anticipated SSD drives and shuts off defrag for these devices automatically. Take a look at this if needed:

http://download.microsoft.com/download/5/E/6/5E66B27B-988B-4...

Sent you a PM.

Received and replied. No worries dude.

If the drive in my Nuvi can wear out from multiple writes and I update my Red Light Camara's and Speed Cameras every 10 days or so, would it be better to use an external flash drive to prevent the internal drive from extra wear? Second question, will an external flash drive run slower than the built in memory?

I think so, external flash drive like sd/ micro sd run alot slower than the built in memory. It's better to update your RLC to sd cause it's cheaper to replace.

You will probably never run up against that limit. If you do, by then the unit would probably need replacing because of other parts dieing.

Check out:
http://downloads.diskeeper.com/pdf/HyperFast.pdf

and Corsair's insight on ssd's:
http://www.corsair.com/_faq/FAQ_flash_drive_wear_leveling.pd...

RT

I remember my mom used to wrap up our TV remote in a foil to protect it against excessive dust and dirty hands. And you know what, at the end we had a broken TV and a "like brand new" TV remote

Strephon_Alkhalikoi]

Know you posted a link but a lot of people do not follow them. I thought I would quote the article to get the discussion in front of readers.

The info presented on your two link's websites conflicts. The first one says that files become fragmented because of numerous writes and their system will fix this problem. The second says that the files are fragmented on purpose to make the SSM last longer. Of course they are both trying to sell something, in the first case its the program that fixes the "problem". In the second its a SSM device designed to last longer.

As I stated earlier, the Windows OS does NOT write directly to a SSM device's memory location. The SSM's on-board controller decides where to put the data, so a defrag is pointless.

I am glad I read the post of everyone on here. When reading the original post I was going to defrag but wanted to wait and see what others said.
I AM SO GLAD I WAITED TO READ WHAT OTHER SAID.
I will NOT be defraging my GPS!!!
Thanks so much to everyone for the great information.

It's apparent you read what you want ... they don't conflict. The first link shows actual testing that reveal how defragging does help; the second link reveals that the rewrite times on ssd's are so large you'll never exceed them by defragging.

"To defrag or not to defrag, that is the question." It's interesting there are so many opinions here on whether defragging decreases the access time, not one that is supported by hard data (except the link above ... which reveals defragging decreases access time). Let's see some REAL DATA on which we can base an educated decision, not just on some unsupported opinions.

RT

I find the first link to be biased. The first is from Diskeeper, which is a well known disk defragmenting program. It's in their best interest to state that solid state memory requires defragging.

The second link is from Corsair, a well known manufacturer of SD cards, USB sticks, as well as RAM. Their article speaks of static vs. dynamic wear leveling. It does not speak of defragmenting and whether it has a benefit or not.

To anyone who doesn't know how a defrag on a hard drive works, it does two things: it takes all the chunks of a file and puts them together, and rewrites the master file table so the pointers to each chunk are correct. On today's large hard drives there is a lot of writing involved in a defragment, especially if the files are heavily fragmented. Defragging a hard drive is important because the head of the drive doesn't have to constantly travel back and forth to find the pieces of the file and put them together into something that can be used. On a standard hard drive, defragging improves the drive's seek time. Since the head doesn't have to constantly travel to find all the pieces of the file, the file is loaded faster and you see an improvement. The improvement is related to the physical motion of the drive head.

On a solid state device, you can run a defrag on it. The defrag will dutifully move the files so they are contiguous and rewrite the master file table as well, just as if it were a regular hard drive. Data in a solid state device is accessed using a built-in drive controller that fetches the data from the appropriate chunks in memory. Unlike a hard drive head, this controller is virtually instantaneous, which is why solid state devices are faster than a hard drive to begin with. Defragmenting a solid state drive doesn't change the access time of the controller. All it does is change the pointers.

I don't believe anyone here has said you CAN'T defragment a solid state device. What I and everyone else have been saying is that there is no benefit to doing so.

I'm not saying this isn't true (not "everyone" agrees, by the way), I'm saying the only REAL DATA we have seems to indicate otherwise. Let's have some REAL DATA to support this opinion. Let's badly fragment a ssd and measure read/write access time. then defrag it and repeat the measurements. Up to this point the only REAL DATA we have is supplied by the link. One can argue any business's info sheet is biased, even the ones who say defragging doesn't help. Again, let's compile some real data!!

RT

This is a great tip but it will not work on my Quest2 that I have on the motorcycle but does work on the 800 series.

Amen!

Retiredtech, you need to re-read those web sites if you think they are saying that SSM needs to be defragged or the access time can be improved by defragging. As stated in Corsair's web site, the location to actually store the data is selected by the chip's on-board controller. Doing a defrag isn't going to accomplish anything.

Do you buy used cars based on what the salesman tells you about the little old lady that used to own it? Both the used car salesman and Diskeeper want to separate you from your money.

Thanks for the tip!

You go right ahead and compile that data. I'll see you in five years or so. *rolls eyes* In the meantime, I'll take the word of an Intel engineer on it. Granted, he speaks of a solid state hard drive and not a flash drive, but his reasoning is sound enough for me to accept.

Source: http://enthusiast.hardocp.com/article/2009/01/13/ask_intel_s...

When there's a conflict of opinion (as we have here), I buy cars based on real data ... not based on some 'know-it-all' unsupported opinion. Why are you against obtaining real data? Are you afraid it won't support your opinion?

I'm open to either way. Being a technician, I need real data. Just saying "Mine now runs faster" or "Didn't help mine a bit" just don't cut it. The same thing happened when discussing WAAS ... only one person did real-time hard data. That's not enough to base an educated decision on. Why can't we get some REAL DATA?

RT

It's probably because we have no way of measuring the differentials or even determining if anything was accomplished.

Thanks for the info

Has anyone tried?? I'm willing to wager, of all the members here, some of them have the knowledge and equipment to accurately measure the required parameters.

Software is available to measure the amount of fragmentation. In Windows, one can set up a "poor man's" test station by using the computer's internal clock to measure write-time. Transfer speed is very easy to measure. Let's give it a try! I'd like to know if it really makes a difference.

RT

I give up! Some people just refuse to learn, their minds are already made up and facts just confuse them. Defrag your solid state memory if it makes you feel better. I'm not trying to sell anything but Retiredtech would rather believe a company who wants to sell him a defrag program. He ignores the recommendation of IT professionals and companies who manufacture flash memory. I suppose that if a company who manufactured copies of Icarus' wings were to issue a white paper that said it was possible to fly as high as you want, Retiredtech would believe it and buy a pair.

If you read what was posted, you'll find I'm open to either position ... I'm just asking for some real data. As of now, the only real data available is what you refer to as 'biased' because it disagrees with your opinion. It may be biased; but as of now, it sure beats the heck out of what seems to be your position ... "I know, so you better believe me!"

RT

I'm with you. I guess the word of an Intel engineer, someone who designs solid state hard drives for a living isn't good enough.

Wow, Thanks for the advice.
Larry

This thread is getting beat, Just do what your going to do, If you believe it helps then defrag your solid state device, if not then don't. It's really that easy, because your going to read info for and against.

I myself, I won't defrag the solid state device, just not beneficial enough to place the writes on it, but that me.

Do you really want to get the thread closed for a heated argument just because one person doesn't agree with your way of thinking of another? Read the tread then do what your going to do.

Read that article again ... nowhere did I see it mentioned that the engineer "designs solid state hard drives for a living". He may be a Mechanical, Civil, or any one of the many different 'Engineers' for all we know. And this article isn't even on Intel's website; does that tell you something?

Let's see if I have this right ... I'm to believe the opinion of this 'possible Intel Engineer' who won't (or can't) provide any supporting real data, but not believe the real data provided by a Diskeeper Corporation Engineer because someone thinks it might be biased? Give me a break.

Of all the years of working with Design Engineers, they were data crunchers ... that was their bread-and-butter, they lived on it ... if they didn't have it, they'd get it. But now this Intel Engineer doesn't provide any real data to support either opinion ... mighty suspicious??

The old saying "Internet: Don't believe half of what you read, and verify the other half." has never been more true than in this case. Until someone steps up and provides the badly needed real data, one "can't verify the other half".

RT

The majority opinion on this thread is that defragging a SSD is a bad idea. Accept it or reject it. I don't give a damn one way or another.

I'm satisfied with the word of an Intel engineer. I'm satisfied with the source I linked to earlier. I'm satisfied with my own personal experience. Many on this thread are just as satisfied. You're not, and you won't be until you get that evidence you so badly need. So go and collect the data and prove it to yourself, because I'm not going to do the work for you.

I'm done with this thread.

Like RT I spent many years working with "Double E's" designing, debugging, manufacturing, selling, and servicing computerized equipment. But I also stop and look at what is being discussed and the reason for taking a proposed action.

The action being proposed is the defragmentation of files stored in a mass storage device. The purpose of the action will be to reduce the amount of time to read and or write to the storage device. All fine and good when you are talking about a storage device that relies on mechanical motion to access the data. So, I pose the next logical question: What mechanical delay is there in accessing any information that may be stored on a solid state device?

None, that I can see. Which brings up the point: what IF defragging speeds up the SSD by 40 or 50 milliseconds? Is that something that we as humans are going to be able to notice? I don't think so.

I think your times are off by an order of magnitude or two. R/W speeds should be in the nano to pico second range not milliseconds. The Sandisk website states: Class 2 cards are designed for a minimum sustained transfer rate of 2 megabytes per second (MB/s), while Class 10 cards are designed for a minimum sustained transfer rate of 10MB/s.

http://kb.sandisk.com/app/answers/detail/a_id/1996/kw/SD%20S...

So a typical Class 2 device will read/write a minimum of 16 million bits every second. Sandisk does not provide any information about access times, but we can probably assume it is at a higher rate than the transfer speed as the addresses increment to pick up the next bit/byte of data.

On the other hand, Seagate states the average access time for one of their Barracuda 7200 RPM disk drives runs around 4.16 milliseconds once the heads complete their average 8.5 millisecond seek time.

http://www.seagate.com/www/en-us/products/internal-storage/b...

Defragging is a waste of time, and possibly harmful to your GPS.

But hey, it's YOUR time and YOUR GPS that you get to waste.

It's a free country. Enjoy.

If I had the luxury of time to sit around with idle time to worry about defragging my GPS, man my life would be perfect.

I'm sure there are not a million other priorities I couldn't think of needing to be done, before this stuff...

Let's qualify that a bit.....based on all the previous posts....ALL of them.

It is VERY likely to be a waste of time UNLESS you are having a problem. If you do it ONLY ONCE, it won't waste much time and it might solve your problem. If it doesn't, nothing lost.

Periodic, routine defragging, however IS a waste of time......over a LONG period of time and a LOT of defrag passes can contribute to premature memory failure AND can cause a catastrophic failure if there is a power loss in the middle of a defrag.

I think that about covers it. If anybody REALLY wants to argue about it further.......I respectfully suggest that you do it somewhere else.

Cheers !!

P.S. Never over-estimate the validity of data or test results that is used in a marketing campaign.

After reading through all the posts placebo effect, IT persons etc! What harm can it do to defrag the SD card or the Garmin.

If you want to defrag do it....please can we get on to something else now....

I've worked with Flash devices for years (the chips) and the type of chips used in Flash cards and USB sticks (NAND Flash) have some basic characteristics that make it difficult to design a FLASH drive that keeps up its speed over time.

1. Before a block of data can be written to the device, the FLASH block to be erased first (if it wasn't erased in the first place).

2. These blocks are grouped together in larger blocks called erase-blocks. ALL the blocks in this group have to be erased at the same time.

3. The erase-block size is far larger than a block (typically 128 or more blocks in an erase-block).

It's probably more complicated than this, but if you imagine these FLASH blocks correspond to disk blocks, as time goes on and the drive is used, eventually you will wind up with:

1. Very few pre-erased blocks available.

2. Blocks from many different files mixed up in the same erase-block.

If a disk block from one file has to be rewritten, the drive does not rewrite the memory block it formerly belonged to, it just uses a new fresh block. Eventually fresh blocks run out, and the drive has to garbage collect the unused but dirty blocks mixed in with the used ones. If the drive is internally fragmented like this, it has to do a lot of erasing and rewriting just to clean things up.

Unfortunately, this is all internal to the drive. The GPSr, windows or whatever may think that the drive is defragmented from its point of view, but internally it is a mess.

The newer SATA SSDs are smart enough to do good, efficient cleanup jobs, but the controller in our teeny weeny SD cards aren't so smart. External defragging will probably just mess up the internal fragmentation more.

So, my opinion is, forget defragging an SD card. Leave it alone.

I greatly improved the speed of my GPS by integrating portions of the temporal lobe of a human brain. Works great!!!

You are NOT telling the whole story DogVomit. Some temporal lobes will actually slow down a GPS, almost like they need to be defraged. You need to carefully select who's temporal lobe you use.

aside from the last couple of very humourous comments I find this thread interesting.

It takes me back to an earlier life during The Dark Ages. I was on a Church Board in Rome and we would sit around and discuss such things as how many angels could dance on the head of a pin.