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Author Topic: What does the disk defragmenter do?  (Read 6754 times)

Offline Chemistry4me

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What does the disk defragmenter do?
« on: 15/02/2009 03:27:27 »
What does the disk defragmenter do? ???
Clean up the computer? How? ???


 

Offline nicephotog

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What does the disk defragmenter do?
« Reply #1 on: 15/02/2009 05:00:19 »
What does the disk defragmenter do?
When files are stored on a storage device from instant request, the file is given a recorded position on the format of the file system table to begin the write to the device.
When the file is allocated the start position it may be larger than the block in the format where a currently stored file is. Because of this it will then need to only write some of the file as a section and then re-allocate a start point on the format of the table of the storage device.
So what you get when your disc/device has had some usae and reusage is broken section of start and finnish of files requiring to have been laid down completely on request.
When the "DEFRAGMENTER" runs on the disc it finds all the file parts for each file, then it makes only one start and finnish point for each file and copies(more shifts) its position to another location where it can be in one complete chunk.

Clean up the computer? How?
Now listen you filthy sloth...
What you need to do is determine how much of that you have on your disc/storage device is really required and mainly whether yo want it.
So you choose in the case of windows whether the files in the "recycle bin" you would ever put back or lose forever.
Or if large files were a wanton laziness to have kept be4cause you no longer have much space in your disc partition.
 

Offline Chemistry4me

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What does the disk defragmenter do?
« Reply #2 on: 15/02/2009 05:33:12 »
Filthy sloth? Was that meant to be a joke? :)
 

Offline nicephotog

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What does the disk defragmenter do?
« Reply #3 on: 16/02/2009 07:45:05 »
Was that meant to be a joke?
Yes.
I am born and raised in Australia, thats a coloquial reverse psychology "joke" as you infer as to its being, No offence intended from a "removed" related part of Britains Commonwealth.
 

Offline Madidus_Scientia

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What does the disk defragmenter do?
« Reply #4 on: 16/02/2009 19:24:11 »
I think I can explain in more laymen terms;

Say you had 1 big book but each page contained a paragraph from 5 completely different books. This would be a pain if you just wanted to read the 1 book, you'd have to go through each page picking out the paragraph from the right book and piecing it together. The books are all in fragments. If one were to defragment this book, one would take all of the pieces of each book and put them all together and have the books read one after the other.
 

Offline Chemistry4me

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What does the disk defragmenter do?
« Reply #5 on: 17/02/2009 02:53:04 »
That makes a lot of sense :)
 

Offline reppel

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What does the disk defragmenter do?
« Reply #6 on: 17/02/2009 13:50:17 »
Whenever you download/delete/edit lots of files or large files, the HDD is likely to get fragmented, which means files are not stored contiguously on the drive. As a result, each time you want to open that file, the HDD has to work even more to gather all the fragments and read it. This is called fragmentation and causes the system to slowdown.
The solution is to defrag the HDD as often as depending on the rate at which it gets fragmented. The defragger will put fragmented files back together contiguously improving data access time and speed.
Its a good idea to run diskcleanup and defrag.
You can either run the Windows program (it needs atleast 15% free space for a defrag) or use a third party tool like Diskeeper which has advanced features like automatic real time defrag, ability to defrag even under 15% free space, system files defrag etc.
 

Offline techmind

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What does the disk defragmenter do?
« Reply #7 on: 17/02/2009 22:54:37 »
What does the disk defragmenter do? ???
Clean up the computer? How? ???

A disk is divided into a very large number of "logical blocks" from start to finish of the disk. The size of a block is fixed, and is typically somewhere between 4kB and 16kB. This block is the smallest chunck of disk-storage that can be addressed for storing user-data.
When you start by copying files onto a clean disk, the system fills the disk sequentially "from the front".
If you then "delete" a file, it's a bit like erasing some pages from a book. You've now got some vacant pages in the middle somewhere. Now erase a few more random files, and there's more blank pages scattered around.
Now say you copy a really big file onto the disk, which requires lots and lots of logical blocks ("pages") it may be that this file gets written across many of the vacant pages scattered throughout the book (logical blocks scattered over the disk). This file is then "fragmented".
(A better system may attempt to put new files in the contiguous free space at the end of the disk if possible, but for large files and as the disk gets full this will cease to be possible).

For related reasons, files which are frequently edited or appended - especially email-inbox files, or "log files" can get fragmented into 100+ pieces.
Reading a heavily fragmented file is much slower than reading a contiguous file as the drive has to fetch all the pieces.

The process of "defragmenting" attempts to move all the files around so that they are all contiguous again, and also to consolidate the free (empty) space into just one large block if at all possible.

Having perfectly defragged a drive however, you could imagine that as soon as any file becomes appended the new bit will have to go at the end of the disk, so the file will immediately become two fragments.

You could envisage that a smart defragger would recognise frequently-used files and log-files and the like and "pre-allocate" each of them some space to grow in their immediate vicinity, to prevent them fragmenting again too soon. I doubt the built-in Windows defragger does this. Third-party ones might ... although I don't know enough about how the OS works to know whether such "smart" defragging would have the intended effect and the "growing space" wouldn't get filled with other junk first...?
 

Offline Chemistry4me

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What does the disk defragmenter do?
« Reply #8 on: 18/02/2009 03:35:59 »
Thanks reppel and techmind :)
 

Offline Vern

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What does the disk defragmenter do?
« Reply #9 on: 20/02/2009 13:41:55 »
Or in Arkansas talk: stuff can get put on the hard drive where bits of each file are scattered all over the surface of the disk platter. The de fragmentation program gathers up all the bits of each file and puts them together in one spot on the drive.
 

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What does the disk defragmenter do?
« Reply #9 on: 20/02/2009 13:41:55 »

 

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