Showing posts with label Defragmentation Utilities. Show all posts
Showing posts with label Defragmentation Utilities. Show all posts

Sunday, January 13, 2013

File Defragmentation Tools for Windows 2003/2008, Redhat/CentOS and Ubuntu

For managing fragmentation of NTFS (Windows Server 2003/2008, XP, Vista, and Windows 7):

For general disk defragmentation, the following utilities offer a substantial improvement in overall performance and efficacy over native operating system tools:
Auslogics Disk Defrag or Raxco PerfectDisk

For use on disks unsupported by the above tools, frequently executed and/or locked files or even a straightforward command line utility that can easily be used as part of a shell script:
Contig from the Sysinternals Suite
Contig has been of particular value when managing backup servers - servers storing huge files with substantial writes on a regular basis. Being able to specify the backup files allows for properly scheduling defragmentation by backup job, and in the process eliminating the need for downtime on these systems as part of this manner of disk maintenance. Can also be used for per-file fragmentation analysis and reporting.

For managing fragmentation of ext4 file systems (newer versions Redhat/CentOS, Ubuntu, Debian, etc):

e4defrag - Linux users (or at least the Linux users I know) have been waiting a long time for the use of an online defragmentation utility. We've all ignored it, pretended as though fragmentation didn't happen on our Linux machines, until the time came for a reboot after 2-3 years of uptime and read/writes forced an fsck that occurred at the worst possible time.

e2freefrag - Provides online fragmentation analysis and reporting by disk, file or mount point.

For managing fragmentation of ext3 file systems  (slightly legacy versions Redhat/CentOS, Ubuntu, Debian, etc)

Good luck! Your options are unfortunately a bit limited.

Many readers may ask: ext3 is a journalled filesystem, why even bother? Primarily, in order to increase IOPS (currently the primary performance bottleneck in terms of price per unit of measurement). Journalled filesystems have seek times just as NTFS does. Reducing those seek times improves performance. Further, unexpected system events can lead to the operating system forcing the journal to be processed. Regular maintenance helps to ensure this process is timely and that downtime is minimized as a result. I have often heard it said that this process "often takes only a second" and as a result can be safely disregarded. While I respect everyone's opinion, I have to very urgently disagree. Most of my experience has been in working in commercial data center environments with several thousand servers. At scale, the statistically insignificant becomes a regular headache. What often happens is part of my concern as an administrator, disaster recovery is just as important in my opinion - safeguarding from improbable catastrophic scenarios and reducing their impact has always been part of my agenda.

That said, let's continue: ext3 requires you to unmount your partition to defragment it. IMO, ext3 is still the most widely used Linux filesystem. I highly recommend the e2fsprogs suite, which includes the following tools:

e2fsck - its just fsck. Not a vulgar typo; performs a filesystem integrity check
mke2fs - creates filesystems
resize2fs - expands and contracts ext2, ext3 and ext4 file systems
tune2fs - modify file system parameters
dumpe2fs - prints superblock and block group info to standard output or pi pe destination of choice
debugfs - a simple memory-only filesystem that can be mounted to perform emergency troubleshooting of your primary filesystem

For defragmentation, you will be typically be using the following:

mount - used to mount and unmount filesystem (also widely known as featuring one of the more chuckle-inducing linux commands when in need of command syntax assistance, #man mount)
fsck - File System ChecK. Checks the specified file system for errors. 
[note: modifying /etc/fstab allows you to specify which devices are mounted]

Some solid non-OS included tools are:

Shake
defrag

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