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Disk Managers:
your Computer's Family Doctor
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(Click the above links for answers. To return, click Go Top
links)
A Hard Disk is a mechanical, magnetic device used to store and
retrieve data on Computers. The storage-retrieval of data need to happen
very quickly, while the Computer is in use, otherwise it would slow down
its operation and make it impossible to work on a Computer. Data is stored
on the Hard Disk in the form of magnetic ‘patterns’. These patterns do
not fade away for many years, thus affording a safe method to permanently
store a Computer’s data.
The
best and most popular manufacturers of hard disk drives are Western
Digital, Seagate, Maxtor (now owned by Seagate), Fujitsu,
Samsung, and Hitachi. IBM used to make hard disk drives but sold that part of its
business to Hitachi.
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Hard Disks have come a long way since they were invented in the
1950s. The first Hard Disks were 20 Inches in Diameter and were called
Winchester Drives, since they were a part of IBM’s then-popular
Computers. They held a few Megabytes of data then.
Having said that, the fact is that Hard Disks have changed very
little in the last 50 years or so. They continue to hold data (only, a few
tens of thousands more of data …), comprise of magnetic platters on
which data is ‘written – much like a Gramophone record (only, their
size has shrunk from the Winchester Drive’s 20 Inches to a mere 5 ¼ and
3 ½ inches now, with Notebook Hard Disks being just 2 ½ inches) and
continue to be the main data storage component of the Computer. What has
not changed is the drive mechanics or the way data is retrieved from the
Hard Disk, what has changed is the way data is passed on to the Computer,
for further processing. This is the Hard Disk Controller and we present
the main types of Hard Disk Controllers in the question Hard
Disk Technologies
A Hard Disk is a very sensitive Computer part due to the following
reasons:
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It is one of the most sensitive parts of the Computer (Notebook or
Desktop), as it contains moving parts with extremely precise movements
– almost like a mechanical watch! The platters of the Hard Disk spin
at very high speeds – today’s Hard Disks spin at a minimum of
5,600 Revolutions per Minute (RPM), with faster Hard Disks spinning at
7,200, 10,000 or even higher RPMs! The Actuator needs to hunt out the
sought data from these high-speed spinning platters! Therefore knocks,
jerks, humidity, dust, very high/ very low temperature, heavy weights
(placing a 10 Kg weight on your Hard Disk is an easy way to kill it!)
– all these damage it very easily!
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A Hard Disk is one of the few Computer parts that have a finite life
– a safe estimate is about 5 years. It may be a year or two more, if
you treat it exceptionally well. Despite all your loving care, it will
‘die’ upon you one day! Most other Computer parts can ‘live on’
almost indefinitely, provided you use them carefully.
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It is the Hard Disk that contains all your data. And, your data is
far more precious to you than your Computer – you can always
purchase a new Computer, but how can you recover the picture you had
saved on your Hard Disk, of your son during his first school play? How
can you recover the important Spreadsheet (or document or presentation
or database) that is critical to your organization? Therefore, any
damage to your Hard Disk not only causes your Computer to come to a
grinding halt, you could also lose financially or emotionally – or
both!
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The picture to the left here shows the parts of an opened-up Hard
Disk.
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The picture to the left shows a Hard Disk with 3 platters and the
Actuator arm, along with parts of its circuitry. Data is written on both
sides of the platters – thus a Hard Disk with 3 platters would have 6
Actuators – one for each surface of the 6 platters.
The Actuator head skims over the surface of the platter - a mere
hair-breadth away - to read/ write data from/ to the Hard Disk. Clearly, a
tiny, single grain of dust can cause the Actuator head to plough a furrow
on the platter, thus damaging it – and your data! |
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Hard Disk errors may be one of the following types:
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Temporary Soft
Errors, which
are caused by errors in the magnetic surface of the Hard Disk platters,
making it impossible to read one or more files on it. Such errors are
easily corrected, either by running utilities such as CheckDisk (with the
/f option) or ScanDisk (both of which come free with Windows and are
excellent as well), or by over-writing the corrupted file(s). Such errors
pose no headaches to you, nor are you required to empty out your wallet!
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Permanent Soft
Errors,
which are caused by permanent damage to the magnetic recording platters of
the Hard Disk. Now, these are real headaches! These errors are more
commonly called ‘Bad Sectors’. Bad Sectors develop over a period of
time, despite all your attempts. If the area occupied by one of your files
develops a bad sector, the file is almost certainly non-recoverable.
Hence, it is vitally important to back up your critical data – more so,
if you have an ageing Hard Disk! Even if your Hard Disk has a few bad
sectors, it is possible to format it, re-install all programs and data and
continue using it for some more time. Formatting marks all bad sectors and
makes sure that data is never written to these ‘marked out bad sectors.’
However, you need to look out for bargain Hard Disk to replace your
current one, as fresh bad sectors will quickly form on the
partially-damaged Hard Disk!
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Hard
Errors
are errors/ damages to the electronics of the Hard Disk. Interestingly, Hard
Errors are easily overcome, since your friendly neighborhood Computer
assembler-seller usually keeps old, damaged Hard Disks. It is easy for a
skilled technician to swap your Hard Disk’s damaged electronics circuit
(called Printed Circuit Board or PCB, it is also called ‘Chassis’ in
some parts of the world – see picture below) with a similar Hard Disk’s
PCB! Note that you cannot swap the PCB of different makes of Hard Disks –
or even different capacities of the same make of Hard Disk! Thus, Hard
Errors should not really cause you headaches, though you need to be prepared
to pay about half the cost of a new Hard Disk, for correcting Hard Errors!
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The picture to the left shows the PCB of a Hard Disk. It is this
that needs to be replaced, if your Hard Disk faces a Hard Error. Notice
the number of components on it – indeed, the circuitry of a modern Hard
Disk is a lot more complex than the earliest Computers!
Now that you know the kinds of errors that your Hard Disk will
develop over the years, make sure you NEVER open up your Hard Disk
yourself, unless you are desperately hunting for reasons to kick yourself!
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Keeping Hard Disks healthy will require you to take the following
precautions/ steps:
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ALWAYS
back-up your vital (maybe even not-so-vital) data - Hard Disks never tell
you that they are planning to die out on you! If you back up your data –
even if the back-up is a few days old – you would not lose too much data!
With DVD Writers becoming common, the DVD has emerged as a favorite medium
for storing large data back-ups quickly and painlessly, while the CD is the
best choice for backing up data up to about 700 Megabytes
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DO
NOT
remove your Hard Disk from the Cabinet (or the Notebook). This is a task for
trained professionals alone
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In case a working Hard Disk is removed, make sure you do not place
any heavy weights on it. Heavy weights will damage the Actuator arm, Spindle
and/ or platters!
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Place
your Desktop or Notebook in a cool environment. It is best not to operate
Computers - Desktops or Notebooks - at room temperatures over 45 Degrees
Celsius or below 0 Degrees Celsius!
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Place your Desktop in as dust-free an environment as possible –
dust kills Hard Disks suddenly!
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Ensure
that your
Hard Disk (and your Computer too) gets clean power – free from Spikes
(sudden increase in voltage) surges (longer high-voltage periods),
black-outs (complete loss of electricity), brown-outs (extended periods of
low voltage) or non-Sine-wave electricity. For, Hard Disks are designed to
run within a narrow band of voltages and frequencies.
A Hard Disk’s performance is measured by means of the following
two parameters:
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Data Rate – This is the number of bytes of data that a Hard
Disk can deliver to the CPU (Central Processing Unit - the Chip), for
processing. Hard Disk Data Rates vary from 5 to 40 Megabytes per second. The
higher the Data Rate, the faster the Hard Disk is
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Seek Time – This is the time taken between the CPU’s
request for data and time when it is actually delivered to the CPU. Seek
Times vary between 10 and 20 milliseconds. The lower the value of Seek Time,
the better the hard Disk’s performance
Apart from the above two parameters, Hard Disks are classified based
on two more parameters, as follows:
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Capacity – This is the total amount of data that a
Hard Disk can store. Hard Disk capacities today are 160 Gigabytes for IDE
Hard Disks to 320 Gigabytes for SATA Hard Disks to over 500 Gigabytes for
SCSI Hard Disks. (More about IDE, SATA and SCSI later on…) The higher the
Hard Disk’s capacity, the more data can be stored on it
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RPM – The RPM is the speed of revolution of the Hard
Disk Platters, measured in revolutions per minute. Today, IDE Hard Disks
have RPMs of 5,400 and 7,200, SATA Drives have RPMs of 10,000 and SCSI Hard
Disks have even higher RPMs.
The data rate or seek times of a Hard Disk do not depend exclusively
on its RPM. It depends on the technology (IDE is slower than SATA, which is
slower than SCSI as well as the circuitry making up the Hard Disk. However for
the same Hard Disk technology, a higher RPM usually does mean smaller Seek Times
and higher data rates.
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Your
Hard Disk consists of multiple platters – 4 platters are shown in the
figure to the right. It is the platters that store your data on its
surface.
The
platters are themselves divided into concentric circles called Tracks.
And, the Tracks are further divided into pie-shaped wedges, as shown in
the figure below and to the right.
Cylinders
are defined as the set of tracks that appear in the same location on each
platter. The diagram here Track X, which consists of the 4 identical
Tracks, one each from its four platters.
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The
Yellow band is a Track, while the Blue arc is a sector, on the platter of
a Hard Disk. The smallest addressable unit of the Hard Disk is the Sector.
Each
Sector contains a fixed amount of data, which is usually 512 Bytes.
Sectors are grouped together to form Clusters – usually 8 Sectors form a
Cluster, therefore you have 4096 Bytes per Cluster.
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Term
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Definition
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Cluster
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The
smallest unit of allocation on a disk. The size of a cluster varies
depending on the file system and the size of the partition
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Defrag
(Software tool)
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A
software utility that reorganizes the data stored on a hard disk so all of
the parts of a file are stored together. Defragmenting a disk speeds up
data retrieval time
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Fdisk
(Software utility bundled with DOS)
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The
utility used to modify partition data and to set partitions to active
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Format
(Software utility bundled with DOS and Windows)
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The
utility used to format a partition. Formatting a partition prepares the
hard disk to accept data
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Fragmentation
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The
naturally occurring phenomenon of file storage in which a file is split
into more than one part when it is stored on the hard disk
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Head
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One
side of a disk platter in a hard drive. A platter is serviced by one
read/write head
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Partition
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A
portion of the hard disk that is grouped into one logical drive for access
by the OS
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Scandisk
(Software utility bundled with Windows)
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A
DOS utility that can verify the integrity of a disk drive and mark any
unreliable areas as bad
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Sector
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A
pie-shaped portion of the disk drive platter surface. Disks are separated
into tracks, sectors, and clusters
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Sys
(Software command utility built into DOS)
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A
utility used to copy the system boot files to the proper location of a
drive partition that has been formatted. The Sys utility makes a disk
bootable
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Track
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The
ring-shaped area on a hard disk, separated by sectors
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So who writes the Sectors, Clusters and Tracks to a Hard Disk? You
can, if you want to – the process is called Low-level Formatting of the Hard
Disk. Low-level formatting of a Hard Disk marks off the beginning and end of
each sector on it. The DOS utility FDISK is a Low-level Disk formatter, there
are other utilities that do this as well.
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During Low-level Formatting, you can also divide your Hard Disk into
Partitions – the process is called Partitioning. Partitioning a Hard Disk
makes it look like you have more than one Hard Disk. It is advisable to
partition your Hard Disk into a Primary, active partition of at least 30 to 40
Gigabytes size, to hold the Operating System and all your Programs. The rest of
your Hard Disk should be used to hold your data files. This partition should
also be at least 30 GB in size, so that it does not run out of space. If you
have more space left over, you may want to keep a third, empty partition. If you
shoot a lot of digital video and need to transfer your video files to your Hard
Disk (to convert into CDs/ DVDs), a large, empty partition will come in handy!
After a Hard Disk is Low-level Formatted and Partitioned, it next
needs to be High-level Formatted as well. High-level Formatting writes critical
information like the file-storage structure, the File Allocation Table (FAT),
etc., thus readying the Hard Disk to hold files and folders. The benefit of
placing the Operating System and Programs in one partition is that if your Hard
Disk is damaged – say by a Virus, you only need to format that partition and
re-install your OS and Programs – your data will remain safe and intact, on
the other partition!
The Primary, Active Partition (the partition that contains your
Operating System) is usually given the Drive Letter C, with the remaining
partitions being named as Drives D, E, etc. The convention is that once all the
partitions of your Hard Disk are labeled by drive letters, the next-available
alphabet is given to your
Optical Drive
(CD or DVD ROM drive) and the letter after that to your removable
USB Drive
. However, Optical Drives (or USB drives, for that matter) can be given any
drive letter from D onwards, even if you have multiple Hard Disk partitions.
The first physical sector of a Hard Disk is special. It contains
what is called the Master Boot Record (MBR), which contains the following vital
information:
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The Boot Program, which tells the Computer that this is a Hard Disk of the
specified capacity. The Boot Program is usually up to 442 Bytes in size.
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The File Allocation Table (FAT), which contains the beginning sector
and other information about the location of each and every file on your Hard
Disk. You can see how important the FAT is – if it is erased/ corrupted,
the files cannot be reached, even though they are safe and actually present
on the Hard Disk! It is as if your address has been wiped out from the face
of your Express Courier letter: your house continues to be where it is
located, but Fed Ex does not have your address, so as to deliver it to your
home!
In fact, the FAT is so important that Hard Disks
permanently retain two copies of it, so that if one is accidentally erased or
corrupted, the other can still seek and retrieve data from your Hard Disk!
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The Disk Signature, which is a unique 4-byte number of the Hard Disk
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The Partition Table, which contains up to 4 entries and holds the
partition information about the Hard Disk
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The
end-of-MBR Market, which always occupies the format, 0x55AA
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Every Postal System needs a directory of addresses, a map of the
city. A Hard Disk too needs such a ‘map’ of its sectors, clusters, tracks
and cylinders. It is the area of the Master Boot Record (MBR) called the File
Allocation Table (FAT) that contains this information - the beginning sector and
other information about the location of each and every file on your Hard Disk.
You can see how important the FAT is – if it is erased/ corrupted,
the files cannot be reached, even though they are safe and actually present on
the Hard Disk! It is as if your address has been wiped out from the face of your
Express Courier letter: your house continues to be where it is located, but Fed
Ex does not have your address, so as to deliver it to your home!
In fact, the FAT is so important that Hard Disks permanently retain
two copies of it, so that if one is accidentally erased or corrupted, the other
can still seek and retrieve data from your Hard Disk!
Running
‘chkdsk /f’
under the DOS Prompt or ‘scandisk’
from within Windows allows the Computer to check the FAT against the actual
location of each file on the Hard Disk, and correct errors if any. Note that the
‘chkdsk’ option without the ‘/f’
switch only checks for FAT errors, without correcting them.
The importance of defragmenting your Hard Disk is also evident from
the structure of the FAT. Suppose you have a file that is 513 Bytes big. Assume
that the first 512 Bytes are written to Sector X. If the last Byte of the file
is written to the very next Sector, the Hard Disk platters or its Actuator arm
need minimum movement alone, to fetch the file in its entirety. However, if it
is written on a different platter – a different Cylinder and on a different
Track, the Hard Disk needs some movement to fetch the file in its entirety. This
not only increases the Seek Time and decreases the Data Rate, it also causes
your Hard Disk to wear out faster! For, all moving parts have a finite life,
thanks to friction!
Also, in case a sector is incompletely filled, the remaining space
cannot be used to hold a different file – a new file will have to be begun on
a new, blank sector. Thus in the example of the file of 513 Bytes size, the
first 512 Bytes will occupy a single sector, while the remaining 1 Byte will
occupy an entire sector, with the 511 Bytes remaining on it being un-utilizable
for storing a second file!
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Although the Hard Disk has evolved very little over the years in
terms of technology, its Capacity has gone up manifold. This has been made
possible due to advances in the FAT structure – one cannot increase the number
of platters too much, since the Hard Disk needs to be fitted into the Computer!
Today's File System is definitely the NTFS system, though we will talk briefly
about the earlier systems as well, in the interests of continuity of content.
Early Operating Systems up to Windows 95 OEM Release 2, i.e., DOS
and Windows 95 Original release, had FATs that were 16 Bits in length. These
were therefore called FAT 16. FAT 16 limited Hard Disk size to 128 Megabytes,
for a Cluster size of 2,048 Bytes. Although up to 512 Megabytes is theoretically
possible if one assumed a cluster size of 8,192, the Cluster size would become
unmanageably large and inefficient. DOS 5.0 and later versions were able to
provide for support of hard disks up to 2 Gigabytes with their 16-bit FAT entry
limit, only by supporting separate FATs for up to four partitions.
With Windows 95 OEM Release 2, it became theoretically possible to
support up to 2 Terabytes, as the FAT system of this release was 32 Bits in
length. This implementation of the FAT is called FAT-32. In practice, Computer
users were able to purchase 5 or 10 Gigabyte Hard Disks, with the FAT 32 system.
Today, Windows NT, XP 2003 and the latest
Vista
editions of Windows have what is called the NTFS (NT file system or sometimes
called the New Technology File System). This has completely replaced the FAT
systems used in DOS and earlier Windows versions, including OS/2’s High
Performance File System (HPFS). NTFS offers a number of improvements over FAT
and HPFS file systems, in terms of performance, extendibility, and security.
Notable features of NTFS include:
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The B-tree directory scheme to keep track of file clusters. (For
more information about B-tree directory structure, click
here)
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Information about a file's Clusters and other data is stored with
each Cluster, not just a governing table, which is the approach used in the
FAT system
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Support for very large files (up to 2 to the 64th power or
approximately 16 billion Bytes in size)
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Provision of Access Control List (ACL) that lets a server
administrator control who can access specific files. (For more information
about ACL, click
here)
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Integrated file compression
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Support for names based on Unicode
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Support for long file names as well as "8 by 3" names
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Data security on both removable and fixed disks
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In Brief, this is how the current NTFS File System works:
When a hard disk is formatted (initialized) under NTFS, its physical
space is divided into partitions or major divisions. Within each partition, the
Operating System keeps track of all the files that are stored by that Operating
System. Each file is actually stored on the hard disk in one or more Clusters of
a predefined, uniform size. Under NTFS, Clusters sizes range from 512 Bytes to
64 Kilobytes. Windows NT provides a recommended default cluster size for any
given drive size. For example, for a 4 Gigabyte drive, the default cluster size
is 4 Kilobytes, and so on. Like Sectors under FAT, Clusters are indivisible
under NTFS. Thus, a file that occupied 4,097 Bytes will be located on 2 Clusters
– the first one containing the first 4,094 Bytes of the file, with a second
Cluster containing only the last 1 Byte of the file – its remaining 4,095
remaining un-utilized for storing any more data!
Cluster size is a trade-off between efficient use of disk space and
the number of disk accesses required to access a file. In general, using NTFS,
the larger the hard disk the larger the default cluster size, since Computer
users would always prefer increasing performance (i.e., fewer disk accesses), at
the expense of some Hard Disk space inefficiency.
When a file is created using NTFS, a record about the file is
created in a special file, the Master File Table (MFT). The MFT is used to
locate a file's possibly scattered clusters. NTFS tries to find contiguous
storage space that will hold the entire file (all of its clusters). Each file also contains,
along with its data content, a description of its attributes, called its
Metadata. For more information on Metadata, click
here.
We have discussed how the File Allocation Table (or Master File
Table, MFT, under the NTFS system) allows for larger data storage on Hard Disks.
The MFT system of NTFS also allows in-built data compression, security and
higher data transfer rates, due to the fact that each NTFS Cluster stores
information about the data it contains. However, it is the Hard Disk technology
used - the circuitry of the hard Disk as it were, that really influences Data
Transfer Rates. In modern Hard Disks, this ‘circuitry’ is built in to the
Hard Disk’s PCB (Printed Circuit Board) itself.
The drive's internal logic board contains a microprocessor and
internal memory, as well as other structures and circuits that control what
happens inside the drive. It is in fact a small PC within the hard disk itself!
The control circuitry of the drive performs the following major functions:
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Control the spindle motor, ensure that it runs at the
correct speed
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Control the actuator's movement to various tracks
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Manage all read/ write operations
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Implement power management features
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Handle geometry translation
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Manage internal cache and optimization features such
as pre-fetch
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Coordinate and integrate the flow of information over
the Hard Disk interface
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Optimize multiple requests
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Convert data to and from the form
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Implement
all advanced performance and reliability features
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We briefly discuss the different Hard Disk technologies below:
There are only three main standards used to interface internal hard
disk drives, CD drives, etc. - the IDE
ATA (Integrated Drive Electronics Advanced Technology Attachment), SCSI
(pronounced ‘Scuzzy’, it stands for Small Computing Systems Interface) and SATA
(Serial ATA) standards. The IDE ATA standard is also called PATA,
which stands for Parallel ATA) and it has been available for many years now. IDE
Drives were the earliest Disk Drive technologies used for Personal Computers.
Even today, IDE Drives form the majority of Hard Disks installed on Computers,
worldwide. It is very likely that if your Computer is a Pentium IV (or earlier
model), your Computer uses the IDE technology.
SATA, which is fast becoming the standard for Desktops and
Notebooks, is available in two versions - SATA 150 (the first version) and
SATA
II 300. They are very similar to the IDE Controllers, yet, SATA is faster than
PATA (IDE ATA). Thus, SATA exhibits higher Data Transfer Rates and lower Seek
Times. SATA Drives are commonly available in RPMs of up to 10,000, (as against
IDE’s 7,200 RPM) further boosting their performance.
The SCSI Hard Disk Controller is significantly different from
IDE
and SATA Controllers. They are also costlier and have been around for some time,
though they have been used exclusively on Servers, high-performance Desktops and
most often, on non-PC platforms such as UNIX machines. SATA drives can
theoretically perform faster than SCSI. This lead to the emergence of a new
SCSI
standard (called SCSI SAS – for Serial Attached Storage), employing a Serial
Controller, much like SATA itself
A brief recap will help us understand Hard
Disk Defragmentation a little better:
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A Hard Disk consists of multiple platters, with each platter being
coated with magnetic media on both sides
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The Platters are divided into concentric circles called ‘Tracks’.
Each Track is divided into little arcs, each capable of holding 512 Bytes
and called Sectors. The Sector is a Hard Disk’s smallest addressable area
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The same Track from each of the Hard Disk’s platters (say Track X)
is called a ‘Cylinder’
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A collection of Sectors (2 or 4 or 8 Sectors) is together called a
Cluster. Files are written to Clusters, with no cluster holding more than
one file – any left-over space is unused and is called File Slack. For
example, if the Hard Disk has 8 Sectors per Cluster, each Cluster would hold
8 x 512 = 4096 Bytes. Thus, a file of 4097 Bytes would be split into 2
Clusters, with the first Cluster holding the first 4096 Bytes of the file
and the second Cluster holding the last Byte: the rest of the second Cluster
CANNOT hold another file’s data
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A file’s Clusters are not always one-after-the-other. In the
example discussed in the previous point, the first cluster may be on Track
42 of the first Platter on the top side, while the second part of the file
may be on the last Platter, last Track! The larger a file, the more ‘fragments’
it may be stored in, on the Hard Disk
File
Fragmentation (also called Disk Fragmentation) results in the following
problems:
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The Hard Disk’s performance is adversely affected, if it is
heavily fragmented. Thus, the Data Access Rate would be sub-optimal and the
Seek Time would be longer than what it should be
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Prolonged operation of a heavily defragmented Hard Disk increases
the wear and tear of its Platters, Spindle and Actuator Arm. This can only
hasten failure of the Hard Disk
Since
it is the Operating System and the Hard Disk’s controller mechanism that
reads/ writes data to the hard Disk, there is nothing you can do, to keep Hard
Disk fragmentation under control. At least, merely by being careful about how
you read/ write data to it!
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The
only solution to reducing Hard Disk fragmentation is the use of Defragmentation
Software. Excellent Software for analyzing the extent of defragmentation of your
Hard Disk is available. They let you check the Hard Disk FAT (or MFT, if it is
an NTFS Hard Disk) for errors, present you easy-to-understand Defragmentation
Reports, give you the right recommendation on what you should do for reducing
fragmentation and the means to carry out the recommendation quickly and safely,
without loss of data.
The
best solutions under this category also let you do the following:
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Run automated Fragmentation checks on specified days/ times, so that
you do not have to rely on your memory alone
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Let you optimize the placement of your Folders (Directories) as well
and not merely your files alone
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Let you specify which files to place first, (you might want to place
all EXE files first), which should be placed next (you might want to put all
DLL files right after the EXE files), which ones to place last, etc.
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Let you defragment your Windows Swap File. The Windows Swap File of
Windows XP is called pagefile.sys and it is located in the root folder of
your Active Partition, i.e., the partition on which your Windows is
installed. The Swap File is huge – about 150% of the physical RAM your
machine has – and therefore, could be broken up into hundreds of
fragments. Defragmenting the Swap File usually leads to significant increase
in Hard Disk performance
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Let
you defragment the other 'Unmovable' files, that are usually left 'as-is' by
not-so-good Disk Managers: the following is a list of unmovable files on
Windows XP Operating System:
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The
Master File Table (MFT), if you are running an NTFS volume and the FAT,
if you are running a FAT 16 or FAT 32 volume
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Metadata
(NTFS File systems)
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Hibernate
File, usually named hiberfil.sys. It is important that you defrag your
Hibernate file, if you are using a Notebook and have enabled Hibernation
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Maybe even load a small portion into memory, thus continuously
working in the background, saving files into contiguous areas as far as
possible: all this in real time and without reducing overall Computer speed,
naturally...
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We
at WellOiledPC
have analyzed the following Four Disk Management Solutions:
Since
the analysis is quite long, we have split it into four pages - one for
each reviewed product, as otherwise, this page would take forever to load!
Click the Product Logos or the Product Names in the table above, for a detailed analysis of each Disk
Manager! |
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Click
here to read about the Disk Manager that has won our Thumbs Up!
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