This article will show you what disk fragmentation is and how to defrag hard drive.
Whenphysical memoryrequired by applications isnt enough, generally the operating system will produce temporary swap file on hard disk.
The disk space occupied by this temporary swap file is used to form virtual memory.
This is the main reason for hard disk fragmentation.
In addition to this, there will be a lot of fragmentations because of temporary files in system.
The temporary files generate when IE Explorer browses information or users directly set them.
Frequent disk defragmentation can enhance the service efficiency of hard drive in computer.
Definition
Disk fragmentation refers to the discontinuous files produced during the process of reading and writing hard disk.
The non-continuous files written on hard disk may produce fragmentation.
Fragmentation will lengthen hard disk seek time and affect system performance.
For example, if virtual memory occupies disk, there will be disk fragmentations on hard drive.
Learn how toDefrag Hard Drive in Windows to Improve Computer Performance.
Generation
In the process of file operations, Windows system might call virtual memory to manage program synchronously.
This will make many programs read and write frequently on hard disk.
Some space will exist on both sides of these two files.
The file will be divided into two parts.
And fragments produce again.
Downloading large files like movies is most common.
During the download, people usually deal with other things.
Downloaded movie files are forced to be divided into several fragments and be stored on hard disk.
So, download is an important reason for fragmentation.
Whats more, frequently deleting and adding files are also reasons for fragmentation.
If the space to hold these files is not large enough, lots of disk fragmentation will be generated.
Along with frequent file deletion, this situation will become increasingly serious.
This is mainly because hard disk needs to jump between multiple pieces when it reads files.
After computer has been used for a long time, disk holds a lot of files.
These files are not saved on contiguous disk space but separately saved in some place.
These fragmented files are called disk fragmentation.
These pieces will lower overall performance of Windows.
Disk contact needs to move back and forth each time it reads and writes files.
This is a waste of time.
So, Windows offers a defragging program.
Search time is called average seek time on hard disk performance index.
It is specified in milliseconds (ms).
The average seek time of disk is less than 9.5 ms. Its the same with reading.
When disk is read, system will check whether the data are in the cache.
If they are, they will be directly read; if not, the disk will be accessed.
This is called reading the disk.
When the same data need to be read for multiple times, cache plays a great role.
But if a file is read for the first time, cache cant do any thing.
Search time and read time largely affect efficiency of program execution.
So, Microsoft adds Disk Defragment to Windows and offers Task Monitor to track disk activity during program startup.
Tracking disk activity makes Disk Defragment work efficiently.
It locates the desired file and saves the monitoring result in hidden directory of drive C:\Windows\Applog.
Most files in this directory use .lgx as extension.
lg represents log file and x meansdrive letter.
For example, the program of drive D: uses .lgd as extension.
Task Monitor only searches for file information during program loading process.
It will adjust and optimize the order based on the loading frequency of the program.
This means that the software used the most times will be optimized best.
The APPLOG.ind file of APPLOG records running times of applications.
This can truly realize improving speed of program startup.
Unless the loading times of ZipMagic is more than that of WinZip.
To solve this problem, users can delete Winzip32.lgx.
If the log file doesnt exist, Disk defragmentation wont optimize it.
External Fragments and Internal Fragments
Many people will be confused with the concepts of file fragmentation and cluster.
Its like that one wall is composed by turning around a block.
The size of cluster can be defined by users when the partition is formatted.
It is usually the size of several KB, such as 8 KB.
800 MB is equal to 80,001 KB.
80,000 KB among it occupies 10,000 clusters.
The rest 1 KB also has to occupy 1 cluster.
However, there is space of 7 KB not used.
And other files cant occupy this cluster which is not fully used.
This causes a little bit of wasted space.
Many people call the waste of 7 KB space as internal fragmentation on disk.
However, users canchange cluster sizeto make the best use of disk space.
The external fragmentation (usually called disk fragmentation.
Disk defragmentation tools can only clean external fragmentation on hard disk.
This is equivalent to that the file is divided and saved separately on discontinuous paragraphs of clusters.
There will be several pieces in accordance with the number of parts that the file is divided into.
So, fragmentation actually refers to file fragments.
This can be understood as the file has been broken into pieces.
Sometimes, sequence between file fragments is disorder.
As a result, a file will be stored on hard disk in a chaotic sequence.
Defragment the Hard Disk
(1).
Necessity
Actually, it should be no doubt that we need to regularly defragment the hard disk.
If hard disk defragmentation really damages hard drive, it will damage it after many times of defragmentation.
Defragmenter collects these fragments and save them on disk as a continuous whole.
Windows comes with this program: Disk Defragmenter.
But there are better such programs in Morton Utilities and Nuts & Bolts.
(2).
You should let computer only launch the Disk Defragmenter to prevent from losing data.
This will affect the service life of hard disk.
