A Tutorial on Disk Defragmentation for Windows NT/2000/XP

A Tutorial on Disk Defragmentation for Windows NT/2000/XP
A Tutorial on
Disk Defragmentation for Windows NT/2000/XP
What You Don’t Know Can Hurt You
April 2, 2002
Table Of Contents
Introduction..................................................................................................................................... 2
Fragmentation 101 .......................................................................................................................... 2
Fragmentation and Performance ..................................................................................................... 3
The Costs of Fragmentation............................................................................................................ 4
Productivity................................................................................................................................. 4
Backup ........................................................................................................................................ 4
System Administration/Help Desk ............................................................................................. 5
Hardware..................................................................................................................................... 5
Myths or Misperceptions ................................................................................................................ 5
Myth 1-Our systems are new, we don’t need defragmentation software. .................................. 5
Myth 2- We have lots of free space so fragmentation’s not an issue. ........................................ 5
Myth 3-Fragmentation isn’t an issue for our workstations......................................................... 6
Myth 4-We use RAID or striping, so we don’t need defragmentation....................................... 6
Myth 5-We are going to use the built-in Windows defragmentation utility............................... 6
Myth 6- A file is a file................................................................................................................. 7
Myth 7- All defragmentation software is the same..................................................................... 7
How Defragmentation Software Products Differ ........................................................................... 7
Windows 2000 API’s.................................................................................................................. 7
Free Space Consolidation ........................................................................................................... 8
Single Pass Defragmentation ...................................................................................................... 8
Free Space Requirements............................................................................................................ 9
Optimization ............................................................................................................................... 9
Master File Table and System Files............................................................................................ 9
Network Awareness .................................................................................................................. 10
Schedule View/Cancel .............................................................................................................. 10
Boot Time Defragmentation ..................................................................................................... 10
NTFS and FAT Directory Consolidation.................................................................................. 10
Page File Defragmentation ....................................................................................................... 11
Auto Update .............................................................................................................................. 11
Command Line Interface .......................................................................................................... 11
Exchange Data Store Defragmentation..................................................................................... 11
Very Large, Very Fragmented Partitions.................................................................................. 11
Windows XP and the MFT ....................................................................................................... 12
Evaluating Defragmentation Software.......................................................................................... 12
Summary ....................................................................................................................................... 13
Appendix 1.................................................................................................................................... 14
Appendix 2.................................................................................................................................... 17
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Introduction
Over the past decade, businesses worldwide have experienced a tremendous expansion of
decentralized, distributed, and networked information processing. Much of this expansion is
based on enterprise versions of Windows-based operating systems like Windows NT or
Windows 2000. A processing paradigm where end users have computing power on the desktop,
and reliance on a network and central server to communicate with colleagues, suppliers, and
customers, has substantially changed the role of the system administrator.
It is not uncommon now for system administrators to have responsibility for hundreds or
thousands of machines, in geographically disparate locations, running all manner of applications
and sharing information over the network. This model stresses the ability of organizations’
system management resources to stay on top of system and application upgrades and service
packs while performing routine system maintenance and sustaining adequate service levels. In
this environment, system administrators need all of the proactive, enterprise-enabled system
management assistance they can get.
Raxco Software has a 22-year history of developing system management software. Since 1997,
Raxco has offered enterprise ready system management for Windows platforms with an
emphasis on Windows NT, Windows 2000, and most recently Windows XP. Raxco, by virtue of
its tenure and track record in this market segment, regards itself as expert in the area of file
fragmentation on the FAT and NT file system (NTFS) that are part of these operating systems.
This paper is provided as an educational instrument that will: explain how and why disk
fragmentation happens, explain the costs of fragmentation, explode some myths about
fragmentation, and examine the differences in disk defragmentation solutions.
Fragmentation 101
Fragmentation is a condition where a file on a disk is in more than one piece. Before we go much
further with this we will address an area that is a little confusing. There are two kinds of
fragmentation. There is logical fragmentation, which is how the file system “sees” the disk; and
there is physical fragmentation, which is how the file actually resides on the disk itself.
Let’s look at an example. You have a Windows 2000 Pro workstation with a 10GB hard drive.
The file system knows the size of the drive and simply views it as a string of Logical Cluster
Numbers (LCN’s) starting at 000000000 and ending at NNNNNNNNN. When an application
creates a file, the file system looks for somewhere to put the file and makes a file entry in the
Master File Table (MFT). The MFT contains pointers indicating the starting LCN for the file,
and a length. If the file is fragmented, the MFT has a series of pointers with a starting LCN and a
length for each fragment. The file is then physically written to the disk by the disk controller. In
a simple example like this, the mapping between the file systems LCN and the Physical Cluster
Number (PCN) is probably a one-to-one relationship. As a disk ages and develops bad sectors,
the mapping between LCN and PCN will change. Alternative disk configurations like stripe sets
and RAID are discussed in-depth a little later.
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Fragmentation happens. It is a normal by product of everyday computer use and it begins the day
you start using your machine, even with a new operating system. It is an unavoidable problem
that affects every workstation and server using Windows operating systems. Fragmentation
occurs under several different scenarios. The most obvious occurs when the file system cannot
find sufficient contiguous free space for a file. One would think that with multi-gigabyte drives
finding contiguous free space would not be a problem. The Microsoft file allocation algorithm is
proprietary, but simple testing demonstrates that extreme file fragmentation can occur even when
there is ample contiguous free space on the disk.
File extension is another source of fragmentation. If a file is extended, and there is no room at the
logical end to grow it contiguously, the file will have to be fragmented. File deletions are the
third contributor to fragmentation. Deletions split the free space and this in itself can contribute
to future fragmentation. We will discuss the significance of free space fragmentation later in this
document.
Think of fragmentation as a computer virus. If a virus occurred that split all your files into
hundreds of pieces, there would be an immediate system slowdown and everyone would want
protection against this ever happening again. Yet, that is exactly what the file system is doing at
a slower rate. Increasingly, file fragmentation erodes system performance, requires more
resources to perform the same task, and increases the total cost of ownership for the
organization. The good news is… it is preventable.
Fragmentation and Performance
As we described above, when an application requests a file, the file system must go and find it.
The MFT is queried and the File ID is found along with the starting LCN and a length. If the file
is in 2000 fragments, the starting LCN and length of 2000 fragments must be located and passed
to the disk controller. In a server environment, the user has access to the processor for a brief
slice of time (a quantum) to complete this task. If the file is so fragmented that all the
information cannot be delivered during the time the user has the processor, he waits until it is his
turn to use the processor again, and finishes reading the file. This wastes system resources and
user productivity. If the file was contiguous, the file system would only have to pass the
controller a single LCN and length and this would likely complete during the user’s initial
processor quantum.
Let’s look at what this means in terms of system performance. Over the years, we have
encountered systems with some very severe problems. One site had ten 10GB partitions each
with about 100,000 files, and many of these had in excess of 11,000 fragments. Another site had
a MFT in 25,000 pieces, while a third had a 339GB RAID partition with 5% free space. While
these cases are extreme, we find that many sites routinely have files that are in several hundred to
several thousand pieces. The improvement in the time it takes to read a file in several hundred
pieces versus a contiguous file can range from 30-80%. When you consider the thousands of files
being accessed every day on a busy server, an average 50% performance increase could come in
handy.
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A simple way to test this at your own site is done with backup. Perform a full disk backup before
fragmentation and time it to completion. Then defragment the disk and time the backup again.
If a representative of Western Digital, EMC, or Winchester called and said there was a new disk
drive that was 50% faster than what you were using today, you would probably be very
interested. Defragmentation software delivers this performance increase on your current
hardware and keeps delivering as the disk fills up, all at a fraction of the cost of new hardware.
The Costs of Fragmentation
International Data Corporation (IDC), in a white paper entitled “Disk Defragmentation for
Windows NT/2000, Hidden Gold for the Enterprise,” estimated that the global cost of
fragmentation is $50 billion annually. There are many factors that contribute to this cost and
some of them are not all that obvious. We will now examine the components of the costs of
fragmentation and how they affect an organization.
Productivity
Defragmentation improves system performance, resulting in improved end user productivity. But
how can this be measured and quantified? Most defragmentation software vendors provide tools
that let you measure the time it takes to read a file before defragmentation and after. Testing has
shown that defragmentation can improve I/O performance by 30-50%. The IDC report says 3085%. If you can improve every I/O on a server by 30%, what is the savings in terms of
productivity?
To answer this, lets look at an organization and make some assumptions. We will first assume
defragmentation can improve I/O by 30%. The organization has 200 users with a loaded hourly
cost of $26. They spend 3 hours a day on their workstations and half that time is doing I/O to the
disk. They work 5 days a week, 49 weeks a year. What is the organization saving in
productivity?
200 users x $26/hr. x 3hrs. x .50 I/O time x 5 days x 49 weeks x .30 gain = $573,300
Improving the access time to each file by 30% can improve server response so that over a half
million dollars of payroll can be utilized more effectively.
Backup
Backup is one of the few operations that actually read an entire disk. As disks grow in size, the
time it takes to perform a full backup will increase proportionally. Many organizations already
face constraints on the time to perform routine system maintenance due to limits on system
downtime.
Defragmentation can dramatically shorten backup times. Independent testing conducted by
Syncsort Inc., the developers of Backup Express, showed that defragmentation could improve
backup times by 30-50% (Appendix 1). Users are generally locked out of the system during
backups. By cutting backup times by one-third to one-half, system availability can be improved.
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If server availability is valued at $100 per CPU hour and the organization saves 5 hours a week
on backup due to defragmentation, the annual savings are $26,000. (Make sure your tape system
is not the I/O bottleneck).
System Administration/Help Desk
When users encounter application or system errors, they call the system administrator or the help
desk. System and help desk personnel are generally highly trained and highly paid technical
resources. These individuals then troubleshoot the problem and affect a solution.
If we assume that our help desk technician has a loaded hourly cost of $30 and it takes them four
hours to diagnose a fragmentation related system or application error, the cost of that error is
$120. If our virtual organization has five such incidents a month, the annual cost is $7,200. These
assumptions are fairly conservative. Ohio Savings Bank, the nation’s tenth largest mortgage
banker, found that regular defragmentation eliminated intermittent application errors and
shortened service calls by three hours (Appendix 2).
Hardware
The most common reaction system managers have to slow system performance is to change the
hardware configuration. A bigger disk does not eliminate the fragmentation problem. The cost
of upgrading hardware to address I/O related performance issues greatly exceeds the cost of
defragmentation software. According to IDC, proactive fragmentation management can help
lower the cost of ownership and help you protect your Windows NT/2000/XP hardware
investment.
Myths or Misperceptions
System administrators face a host of challenges in keeping a networked Windows environment
up and running. They are expected to know the operating system, the network protocols, dozens
of applications, security, hardware configurations, and a myriad of other things associated with
keeping the enterprise’s IT resources going. It is therefore understandable that there could be
some misunderstandings about how defragmentation software works and what it is doing to your
system. The purpose of this section is to debunk some common myths and clear up
misperceptions about defragmentation software.
Myth 1-Our systems are new, we don’t need defragmentation software.
Fragmentation begins when you start using the system. If you take a brand new machine and
install Windows 2000, Internet Explorer, Microsoft Office, and PerfectDisk 2000 (so you can
analyze the disk) you will find over 300 fragmented files on the system and all you have done is
install software. While fragmentation is not a problem at this time, it is a condition that will get
worse with time and usage. Just like you go to the dentist to avoid serious tooth and gum
problems, you should proactively manage fragmentation so it never becomes an issue.
Myth 2- We have lots of free space so fragmentation’s not an issue.
The amount of free space on a disk has nothing to do with fragmentation. If you have 30GB of
free space on a 40GB drive, but you have 10GB of frequently changing files that are in hundreds
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or thousands of pieces, your machine performance can be adversely affected by fragmentation.
In most cases, system administrators have no idea about the condition of the files on their
system.
Myth 3-Fragmentation isn’t an issue for our workstations.
There is a belief that defragmentation is not necessary on workstations. Windows NT/2000/XP
workstations use the same file system as their counterpart servers, and fragmentation is a
function of file system use. Many organizations have adopted policies requiring saving all data to
the servers. While this ensures data integrity and protects data, it does not preclude users from
saving files locally. Other file activity, like extension and deletion, also contribute to
fragmentation on the desktop.
Windows XP posesses some unique features that also contribute to fragmentation. The growth of
the layout.ini file can challenge the abilities of the built-in defagmenter. The built-in tool makes
no attempt to clear out free space to ensure defragmentation of the applications referenced in
layout.ini
The System Restore function fragments the free space on the disk. Since the built-in
defragmenter does not consolidate free space, file fragmentation will occur at a faster rate on
workstations with this feature enabled.
In a Windows XP white paper1, Microsoft contends that fragmentation is a performance-robbing
problem and frequent defragmentation is the only available solution.
Myth 4-We use RAID or striping, so we don’t need defragmentation.
This is one of the most common misperceptions about defragmentation. As was noted in the
Fragmentation 101 section of this document, there is “logical” fragmentation and “physical”
fragmentation. In a RAID environment the file system has to locate the logical pieces of a file
and pass them to the RAID controller. If the file is in 2000 logical fragments, the file system will
have to pass 2000 separate I/O’s to the controller. With defragmentation, that effort can be
reduced to passing a single logical I/O to the controller. In testing using the ZD Server Bench
and the Intel IOMeter benchmark suites, we have seen defragmentation double the transaction
rate of both reads and writes to the disk in a RAID environment.
With RAID, a file that is logically contiguous will almost certainly be physically fragmented.
The testing proves that a contiguous logical disk delivers twice the performance of a fragmented
logical disk, regardless of the condition of the physical disk.
Myth 5-We are going to use the built-in Windows defragmentation utility.
If you are working at home on a single workstation, this is probably all you need. The built-in
defragmentation utility is woefully inadequate for enterprise use. Some of the shortcomings of
the built-in utility are:
1
Sechrest, S. and Fortin, M. “Windows XP Performance”. URL:
http://www.microsoft.com/windowsxp/pro/techinfo/planning/performance/evalissues.asp (June
2001).
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It cannot be scheduled to run over the network
It can only defragment a single partition at a time
It cannot move certain file types so it never completely defragments the disk
It requires Admin privileges so you have to physically go to each machine to run
It may require multiple passes to defragment and does not consolidate the free space.
Busy administrators simply don’t have the time to bother with a partial solution like the built-in
defragmentation tool.
Myth 6- A file is a file.
Not exactly. With Windows NT/2000/XP, there are a number of different types of files, and
different defragmentation software moves these files with varying degrees of completeness,
depending on the operating system in use. Under Windows NT/2000, you need to do a boot time
defragmentation to move the Master File Table (MFT), the related metadata files, and the page
file. Windows NT can only move the directories at boot time. With Windows XP, the MFT can
be moved online, but certain metadata files still need to be moved at boot time only. This is
important because if the MFT, metadata files or other system files are not defragmented, it is
very unlikely you will ever be able to completely defragment a disk. The unmovable fragments
will cause data files to be split around them.
Myth 7- All defragmentation software is the same.
Different software vendors take different approaches to the defragmentation problem. Speed
versus quality, multi-pass versus single pass, and interval versus event driven, all affect the final
outcome. As a user, you need to determine which product best fits your needs and delivers the
best results in your environment. The best way to determine this is to test solutions head to head,
and compare their results and their utility. To help you understand the differences between
defragmentation offerings, the next section compares and contrasts two products that approach
defragmentation differently.
How Defragmentation Software Products Differ
All defragmentation software is not the same. How different products behave can have a
significant effect on your systems. This section identifies some of the criteria you may want to
consider when evaluating defragmentation software for your organization. It also describes how
two different products address these criteria. The products compared are Raxco Software’s
PerfectDisk® 2000 and Executive Software’s Diskeeper® 7.0.
Windows 2000 API’s
Safety is a primary concern when you are moving files around a disk. Protection against data loss
or corruption must be absolute. Microsoft offers a special Application Program Interface (API)
that affords this protection to online defragmentation software vendors. The API’s also guarantee
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plug-and-play compatibility with version changes and service packs. The vendors, through the
API’s, implement defragmentation strategies/algorithms that determine where and when to move
files or free space.
PerfectDisk 2000 uses the Microsoft developed API’s to perform its online defragmentation.
Diskeeper also uses the API’s for its online defragmentation.
Free Space Consolidation
The file system is more efficient if it can find contiguous free space from which it can allocate
space to create files contiguously. Free space fragmentation causes file fragmentation and
necessitates running defragmentation software more often.
PerfectDisk 2000’s defragmentation algorithms favor consolidating all the free space into as
large a piece as possible. This approach was taken because the Microsoft API’s under Windows
NT 4.0 and Windows 2000 offered different levels of granularity for a file move. By
consolidating the free space, PerfectDisk can move larger files and get better file “packing”. Free
space consolidation also reduces the amount of free space required to completely defragment a
disk in a single pass. The system performance benefit is that if the file system can find
consolidated free space, new files will be created contiguously, and re-fragmentation will occur
at a slower rate.
Diskeeper’s algorithms appear to favor file defragmentation over free space consolidation. While
this approach seems to provide a slight speed advantage, it fragments the free space. Depending
on the version of the API’s in use, many of these free space fragments are not usable by the API,
so eventually Diskeeper runs out of usable free space and the only alternative is to quit and start
over, or manually create additional free space by removing files. This is the idea behind the
multi-pass defragmentation approach.
Single Pass Defragmentation
Many sites have a limited window of time for system maintenance. Running a defragmenter
several times to get an acceptable result is not an option. The Microsoft API’s support the ability
to completely defragment a disk in a single pass.
PerfectDisk 2000 defragments 99-100% of the data files on a partition in a single pass, even in
low free space conditions.
Diskeeper will defragment in a single pass provided the files or the free space are not too
fragmented, and there is ample free space (>20%). If the files or free space are too fragmented,
Diskeeper will employ a multi-pass approach. If the file or free space fragmentation are very
severe, or the free space too limited, Diskeeper may never completely defragment the partition.
The time PerfectDisk 2000 requires to do a single pass defragmentation and consolidate the free
space is less than the aggregate time Diskeeper requires to perform a similar quality job.
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Free Space Requirements
All defragmentation software requires some free space to operate. With today’s large partitions,
a small percentage of free space can be a significant amount of storage. While it is not advisable
to fill disks to capacity, defragmentation can be performed on very full partitions. In fact, these
are likely to be the partitions that need defragmentation the most.
PerfectDisk 2000 will defragment a partition with as little as 5% free space outside the Master
File Table reserved zone (prior to XP, defrag software could not use the MFT reserved space).
Diskeeper recommends a minimum 20% free space (outside the reserved zone) to run. If there is
less than 20%, Diskeeper issues a message suggesting you remove files from the disk to free up
space, and then run Diskeeper again.
Optimization
Where files are located on a disk can make a difference in performance. A Microsoft white paper
addresses how performance is affected by where the Master File Table is on a partition. This is
referenced later in this section.
PerfectDisk 2000 employs a patented disk optimization strategy that intelligently positions files
according to their usage. The strategy suggests that if files that are not changing are
defragmented and grouped together, they do not need to be moved on subsequent
defragmentation runs. This means subsequent defragmentation passes take less time and
resources. Free space consolidation is also part of the optimization scheme.
Diskeeper file placement is purely random and the free space is fragmented all over the disk. The
random placement means a lot of files must be moved to defragment the files that changed since
the last defragmentation pass.
PerfectDisk 2000 defragments files, consolidates free space, and optimizes the disk in less time
than Diskeeper only defragments.
Master File Table and System Files
Under Windows NT/2000, the MFT, it’s associated metadata files, and certain system files need
to be defragmented offline by a boot time defragmentation. If these files are not defragmented,
data files may need to be “split” around them making a complete online defragmentation
impossible. With Windows XP, a boot time defragmentation is only needed to handle the page
file, hibernate file, non-MFT metadata files, and directories on FATxx partitions.
PerfectDisk completely defragments the MFT, all the metadata files, and the system files. It also
reports accurate status of these files in its statistics.
Diskeeper does not defragment all the metadata files and it does not report on their status. If
metadata files are fragmented, Diskeeper does not report it. In some cases, Diskeeper does not
completely defragment the MFT.
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Network Awareness
Enterprise defragmentation is the ability to schedule and run defragmentation events anywhere in
the network from anywhere in the network.
PerfectDisk 2000 can be scheduled over the network from both the workstation and server
licenses.
Diskeeper supports network scheduling only from a server license.
Schedule View/Cancel
An administrator will want to view and possibly modify defragmentation schedules in
consideration of other system tasks. The ability to quickly access this information gives the
administrator a quick response mechanism to changing system requirements and the ability to
balance resources.
PerfectDisk 2000 supports a Scheduling Wizard that lets an administrator view or cancel
schedules on any machine in the network, from any machine in the network. With the most
recent release, schedules can also be modified.
Diskeeper requires that network schedules be viewed/cancelled only from the machine on which
the original schedule was set.
Boot Time Defragmentation
As we noted above, a boot time defragmentation is required under Windows NT/2000 to
defragment the MFT, metadata, and system files. Enterprise defragmentation should support the
ability to perform boot time defragmentation on remote machines from one or more schedules.
PerfectDisk 2000 can schedule a boot time defragmentation pass on multiple systems at the same
time. Under Windows NT/2000/XP, PerfectDisk 2000 uses the boot time option to explicitly
position the MFT according to Microsoft’s recommendation. On data partitions, PerfectDisk
2000 does not require a reboot if it can get an exclusive lock on the partition. System partitions
always require a reboot.
Diskeeper’s boot time defragmentation can only be scheduled on a single system at a time.
Diskeeper requires a boot time defragmentation on both system and data partitions.
NTFS and FAT Directory Consolidation
Directory defragmentation and consolidation moves these files and their fragments out of the
way so the online defragmentation engine can do the best possible job of defragmenting the
partition and avoid splitting data files.
PerfectDisk 2000 defragments and consolidates directories on NTFS and FAT partitions.
Diskeeper does not consolidate directories on NTFS.
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Page File Defragmentation
PerfectDisk 2000 can defragment the page file regardless of the amount of free space on the
partition.
Diskeeper requires free space equal to the size of the page file.
Auto Update
Auto Update has no impact on system performance. It is an automated mechanism that ensures
you have a product’s most recent version.
PerfectDisk 2000 has an Auto Update feature whereby updates can be automatically downloaded
from our web site, or redirected to an internal site prior to distribution.
Diskeeper has no Auto Update capability.
Command Line Interface
A Command Line Interface (CLI) eases the integration of the defragmentation process and
scheduling with other system maintenance job streams like backup.
PerfectDisk 2000 has a full-featured Command Line Interface supporting the integration of both
local and network defragmentation commands in your own scripts. PerfectDisk 2000 can run the
CLI and the GUI at the same time.
Diskeeper provides a limited CLI with only local defragmentation support. If you are running the
Diskeeper CLI, you cannot run the GUI, and vice versa.
Exchange Data Store Defragmentation
Microsoft recommends the periodic offline compaction/defragmentation of Exchange data stores.
This activity improves Exchange performance by re-indexing the data stores and reclaiming disk
space. Exchange defragmentation is generally a manual, time-consuming, and cumbersome task.
PerfectDisk 2000 has an additional module that automates the offline
compaction/defragmentation of Exchange data stores.
Diskeeper has no Exchange compaction/defragmentation support.
Very Large, Very Fragmented Partitions
Defragmenting very large, very fragmented partitions is a special problem and one particularly
related to enterprise RAID configurations. The primary issue is performing the task with a
minimal impact on resources and within an acceptable timeframe. The number of files, number
of fragments, and the amount of free space can all impact the time it takes to defragment a large
partition.
While defragmenting large partitions is a challenge, defragmenting large files also poses a
challenge. With an increase in multi-media presentations, animation, and the built-in digital
video editing capabilities in Windows XP, files over 1GB will not be uncommon. The viewing of
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digital video or multi-media presentations can be adversely affected if fragmentation interrupts
the streaming of the file to the processor.
PerfectDisk 2000 Version 5.0 has been specifically designed to efficiently defragment partitions
of 100GB to greater than 1TB. The new design delivers quick file movement, low memory
footprint, and less CPU usage than other products. While single pass defragmentation is still the
preferred approach, some sites may have specific situations where a large partition cannot be
defragmented in the time allotted. PerfectDisk 2000 Version 5.0 provides better stop/restart
capability that lets defragmentation benefits accrue, even when the defragmentation task is
interrupted.
During the development of PerfectDisk 2000 5.0, we ran a stress test on an IDE controlled
300GB partition with 1,000,000 files, 4,500,000 fragments, and 12% available free space. The
machine had a 1 Ghz processor with 512MB of RAM. The disk had no MFT or system file
fragmentation. This is not your average partition. PerfectDisk 2000 defragmented this partition in
42 hours elapsed time and used 4 hours of CPU.
Our only experience with Diskeeper 7.0 was on this same partition. Diskeeper 7.0 defragmented
the partition in 108 hours elapsed and used 50 hours of CPU. The Microsoft newsgroups are a
good alternative source of information for other user experiences with large, fragmented
environments.
Windows XP and the MFT
With the advent of Windows XP, Microsoft documented a finding that states that locating the
Master File Table approximately one-third of the way down a volume delivers a 5-10%
performance increase.
Only PerfectDisk 2000 explicitly positions the MFT in this location on Windows NT/2000/XP
platforms.
Evaluating Defragmentation Software
The best way to determine which defragmentation solution is the best for your environment is to
evaluate them on your systems. The first thing you need to do is ensure that you run both
products against exactly the same disk. To do this, you will need a disk-imaging tool like
Norton’s Ghost® or PowerQuest’s Disk Image™. These tools ensure that you have at least two
disks that are sector-by sector copies.
Install the defragmentation software you want to evaluate. Run the Analysis phase of one of the
products against the disk you want to defragment and note the total number of files and the
number of fragmented files. Identify the “Most Fragmented Files” and note how badly
fragmented are the worst files. Also note the condition of the free space on the disk. Is it
fragmented or contiguous? Disk defragmentation software is only as good as your worst disk.
Choose a disk that has badly fragmented files and/or limited free space. You want to make sure
the product you select can defragment just about anything.
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Once you understand how bad the problem is on your target disk, run one of the defragmentation
products and time it to completion. Vendors make suggestions on the running order of the boot
time and online defragmentation. Follow the suggestion of the product vendor. Run the second
product on the cloned disk and do the same. When the products are finished, review the reported
statistics by looking at the same information you evaluated before the defragmentation. Things
you will want to look for are:
Did the boot time defragmentation completely defragment the MFT, metadata, and system files?
Did the online defragmentation completely defragment the data files?
Is the free space fragmented or consolidated?
Was the time to complete acceptable?
An interesting exercise to validate your results is to cross check the statistics with both products.
For example: if you defragment a disk with product A, view the results with both product A and
product B interfaces. There may be some disparity in file counts due to how each vendor counts
directories and subdirectories, but between the two sets of statistics you will get a very good idea
of the quality of the job done.
Summary
While enterprise disk defragmentation sounds relatively simple, it is clear that one’s choice of
technology can have a profound impact on user productivity and system performance, as well as
ongoing system administration and support costs. The right product is the one that reliably and
consistently delivers the best results under the worst conditions. Proactive defragmentation
protects the user’s investment in the platform, lowers the total cost of ownership, and delivers
customer satisfaction.
Copyright 2002, Raxco Software, Inc. All rights reserved.
PerfectDisk is a registered trademark of Raxco Software, Inc. Executive Software and Diskeeper are trademarks or registered
trademarks of Executive Software International. Microsoft, Windows, NT, and XP are trademarks or registered trademarks of
Microsoft Corporation. All other trademarks or trade names are the property of their respective owners.
13
Appendix 1
Syncsort’s Backup Express Partners with Raxco Software to
Speed Backup with PerfectDisk 2000
Combination of Leading Disk Defragmentation and Optimization Utility and Backup Solution
Improves Backup 30% - 50%
GAITHERSBURG, MD, October 23, 2001 – Syncsort Incorporated, the respected developer of
high-performance backup and data warehousing software, and Raxco Software, Inc., a leading
provider of systems management utilities, have entered a joint partnership offering two of their
products in tandem. Recent benchmarks have shown that using the combination of Raxco’s
PerfectDisk 2000 and Syncsort’s Backup Express can speed backup up to 50% over baseline.
After extensive testing of Raxco’s PerfectDisk 2000, Syncsort determined that backup speeds
can be improved by 30% - 50% by first defragmenting drives with PerfectDisk 2000. “With
PerfectDisk 2000, we’re assured that data files and all metadata files are defragmented in a single
pass, which no other defragmenter can do,” said Winston Hait, senior product manager for
Syncsort. “In addition, PerfectDisk 2000 optimizes the disk, resulting in consolidated free space
and a reduced rate of refragmentation that saves even more time and resources. PerfectDisk
2000 for Exchange helps further by compacting and defragging Exchange data stores.”
“As the leader in defragmentation and optimization, Raxco Software is delighted to be
partnering with a company with the stature of Syncsort,” said Jim Williams, Windows® product
manager for Raxco Software. “The addition of Syncsort as a Raxco partner solidifies our
position as the leader in this field and provides another channel for PerfectDisk 2000. The
advanced capabilities of PerfectDisk and Backup Express will provide a powerful disk and
backup management solution for customers demanding high performance and superior quality in
their enterprises.”
14
Fragmentation and Backup Speed
File fragmentation is a normal by-product of using a computer, occurring when files cannot be
created contiguously or when file deletions or truncations cause “holes” of free space.
Fragmented files take longer to read, and so slow data streaming, and therefore the backup
process. For read-intensive applications like backup to realize their optimum performance, the
files should be as contiguous as possible.
About Backup Express
Syncsort’s Backup Express is an advanced, enterprise-wide backup and restore solution that
supports NAS, NDMP, Storage Area Networks (SANs) and other network configurations. Its
distributed architecture allows it to back up to any device in the network whether it is running
UNIX, Windows, or NetWare, while maintaining a single central catalog for the entire
enterprise. Backup Express can cluster tape drives, including large automated libraries, at any
server on the enterprise; dynamically allocate drives within a SAN; provide three different
backup options for NDMP-based systems; keep sensitive data off the network; and allow on-line
backups of large database servers such as Oracle, SAP, MS Exchange, and SQL Server.
About PerfectDisk 2000
Raxco Software’s PerfectDisk 2000 is a complete enterprise disk defragmentation solution.
PerfectDisk 2000 was engineered as an industrial-strength defragmentation solution for today’s
distributed Windows networks. PerfectDisk 2000 is fast, thorough, scalable, flexible and safe.
Among its features are:
•
Completely defragments files in a single pass
•
Defragments all 16 Metadata files, including the Master File Table
•
Consolidates free space and organizes disk according to usage patterns to slow future refragmentation
•
Automates the defragmentation of Exchange data stores
•
Provides threshold management to prevent unnecessary defragmentation runs
•
Offers a Network Scheduling Wizard to let users set, view and cancel schedules
•
Provides offline defragmentation of the MFT and system files that is fully automated and
requires no human intervention.
15
About Syncsort
Syncsort Incorporated is a leading developer of high-performance data warehousing software for
mainframe, UNIX, and Windows environments. For more than 30 years, Syncsort has built a
reputation for superior product performance and reliable technical support. An independent
market research firm has named Syncsort as one of the top Data Warehouse 100 Vendors for
three years in a row. Over 95 percent of the Fortune 100 companies are Syncsort customers, and
Syncsort’s products are used in more than 50 countries to back up and protect data in distributed
environments, speed data warehouse processing, improve database loads and speed query
processing. For more information, visit the Syncsort web site at www.syncsort.com.
About Raxco Software
Raxco Software is a leading software engineering company that has been offering system
utilities for more than 20 years. Its PerfectDisk 2000 is Windows 2000-certified and designed for
Windows XP, and works on Microsoft Windows 95/98/Me/NT/2000/XP systems. Raxco also
makes other products for Windows operating systems and suites of utilities for Compaq
Computer’s OpenVMS operating system. Raxco Software can be found on the Web at
www.raxco.com.
###
Editorial Contacts:
Joe Abusamra
Raxco Software, Inc.
(301) 519-7835
[email protected]
All brands or products are trademarks or registered trademarks of their respective holders.
16
Appendix 2
Ohio Savings Bank Increases Licenses
Of Raxco’s PerfectDisk® 2000 Defragmenter
By 19%, Bringing Total to 2,210 Copies
Ability to Schedule Automatic Defragmentation Runs and Flexible Options
Called Key to Selection; Weekly Defragmentation Achieves an Average 30%
Performance Increase and Three Hour Reduction in Trouble Ticket Response
GAITHERSBURG, MD, July 10, 2001 – Raxco Software Inc. today announced a follow-on
order from Ohio Savings Bank that has increased to 2,210 the number of copies of Raxco’s
PerfectDisk® 2000 defragmenter that the bank uses. Regular defragmentation with PerfectDisk
2000 has helped the bank increase the performance of its workstations by 30 percent, and has
reduced the time it takes to answer support calls by three hours per call.
The Cleveland-based bank, with nearly $10 billion in assets, is one of the largest financial
institutions in Ohio, Florida, and Arizona, and the tenth largest wholesale mortgage lender in the
United States.
The bank began using PerfectDisk two years ago, when it began migrating from the Windows®
95 operating system to Windows NT. Today, although the majority of its workstations use
Windows NT, PerfectDisk 2000 also supports computers running Windows 98 and Windows
2000.
Ohio Savings Bank selected Raxco’s PerfectDisk 2000 because of its flexible scheduling options
said Jody Graff, Desktop Planning Manager. “We like its ability to defragment disks on a
scheduled basis. PerfectDisk allows us to choose the automatic scheduler, let the user schedule
the disk defragmentation, or have a technician complete it while visiting the site. This flexibility
allowed us to change our approach to meet new business requirements,” she added.
The bank has hundreds of applications running on approximately 1,500 workstations that are
locally connected. Remote installations consist of laptop units using dial-up lines and units
17
connected through a virtual private network. The workstations are scattered throughout the
several states in which Ohio Savings Bank does business.
Graff initially used PerfectDisk as a way to address user complaints about decreased
performance. “Many of our Bank applications are file intensive, requiring large data downloads.
This results in a lot of file movement, and this type of file manipulation often leads to file
fragmentation,” she said. “We found that if we ran PerfectDisk once a week it would improve
performance by an average of 30 percent.” Another benefit was that defragmenting disks often
eliminated intermittent application errors on individual machines. “The errors disappeared after
we ran PerfectDisk,” Graff said.
Graff pointed out that PerfectDisk’s flexibility enables the bank to set up a defragmentation
scheme that matches the schedules of individual users. “Users who dial in disconnect or shut
down their laptops at night, so we can’t defragment their systems automatically,” she said.
“PerfectDisk allows us to run in a mixed environment, where locally attached systems can be
defragmented automatically overnight, and remote systems are defragmented by the users when
it’s convenient for them.”
File fragmentation is a normal by-product of using a computer. It occurs when the computer’s
file system cannot find enough free space on the disk to create a file or extend an existing file in
one piece. If there are files on the system that are changing on a regular basis, it is possible these
files can be in hundreds or thousands of pieces all over the disk. Fragmentation can cause a
computer to use excessive resources to complete tasks related to reading and writing files. This
unnecessarily increases the work the computer must do to support the applications being run.
PerfectDisk 2000
Raxco Software’s PerfectDisk 2000 is a complete enterprise disk defragmentation solution.
PerfectDisk 2000 was engineered as an industrial-strength defragmentation solution for today’s
distributed Windows networks. PerfectDisk 2000 is fast, thorough, scalable, flexible and safe.
Among its features are:
•
Defragments all data files in a single pass
•
Defragments all 16 Metadata files, including the Master File Table
18
•
Consolidates free space and organizes disk according to usage patterns to slow future refragmentation
•
Automates the defragmentation of Exchange data stores
•
Threshold management prevents unnecessary defragmentation runs
•
Network Scheduling Wizard lets users set, view and cancel schedules
•
Offline defragmentation of the MFT and system files is fully automated and requires no
human intervention
About Ohio Savings Bank
Ohio Savings Bank was founded in Cleveland, Ohio in 1889. Since then, the bank has grown to
nearly $10 billion in assets, and is one of the largest financial institutions in Ohio, Florida and
Arizona, and the 10th largest wholesale mortgage lender in the United States. Expansion into
Florida began more than 10 years ago with the inception of its AmTrust Bank division. Today,
there are 15 AmTrust Bank branches located throughout southeast Florida. In 2000, the first
AmTrust Bank branch opened in Phoenix, Arizona, with two more opening in the first half of
2001 and a fourth planned for later this year.
About Raxco Software
Raxco Software is a leading software engineering company that has been offering system
utilities for more than 20 years. Its PerfectDisk 2000 is the only Windows 2000-certified
optimized defragmenter that works on Microsoft Windows 2000, Windows NT, Windows
Millennium Edition, and Windows 98/95 operating systems. Raxco also makes other products
for Windows operating systems and suites of utilities for Compaq Computer’s OpenVMS
operating system.
###
Editorial Contacts:
Joe Abusamra
Raxco Software, Inc.
(301) 519-7835
[email protected]
Edgar E. Geithner
g.m marketing communications
(508) 875-3821
[email protected]
All brands or products are trademarks or registered trademarks of their respective holders.
19
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