PerfectDisk
PerfectDisk is the name of separate but related defragmentation utilities for Windows and HP OpenVMS published by Raxco Software. It has won several awards from computer magazines,[1] and is certified by Microsoft for all its current NTFS-based operating systems.[2] The current version is PerfectDisk 12.
The OpenVMS version of PerfectDisk, still in production, predated the Windows version by several years and contributed much of the approach adopted by the Windows versions. It was developed by William Davy and operates on the Files-11 file system used by OpenVMS. It features a single-pass, four-phase algorithm, intelligent placement (moving infrequently-accessed data to the periphery of the disk to reduce average seek distance,) locating directory files near indexf.sys (the Files-11 counterpart to the FAT or MFT) and clustering of "volatile" files, which attempts to make a file deletion more likely to occur adjacent to existing free space. It was the first defragmenter capable of defragmenting an open file that was actively being written, by combining the defragmenter with specialized functionality of Raxco's Data Caching product, PerfectCache, forming a product called UltraDisk.
In the mid-1990s, Raxco assigned several developers to create a Windows version of the defragmenter. Since the original product was written in VAX Macro (assembly language), starting from the existing source code was not a viable solution. Instead, the defragmentation strategy, which was largely applicable to Windows file systems despite coming from a different operating system, was refined and applied to a new code base.
PerfectDisk has editions designed for most user categories, from home PCs to large servers. In addition to defragmenting files, it also optimizes disk drives with an optimization strategy called SMARTPlacement.[3] It defragments data and system files and places a high priority on free space consolidation.
Features
PerfectDisk attempts to defragment drives in a single pass of a drive, as opposed to a common approach of running continuously and gradually defragmenting the file system.[4]
PerfectDisk has the capability of a scheduled defrag managed by an internal task scheduler.[5] It also offers the option to defrag during screen saver activity, or when the PC is idle.
In 2007 it was the first utility to support defragmentation of terabyte-sized drives. Enterprise features include integration with Active Directory, enterprise-wide defrag management and reporting. More recently the product has added support for defragmentation of virtual environment files and images.[6]
The Boot-time defrag facility is capable of defragmenting Windows meta data,[7] Master File Table, hibernation file and page file. It was the first utility to offer Free Space defragmentation, and the SMARTPlacement algorithm places older (program) files near start of the drive, and newer (data) files near the end of the drive, closer to free space in order to minimize refragmentation.[8] This optimization strategy aims to organize files by usage, resulting in a slower rate of refragmentation and also fewer resources being consumed.
Editions
The PerfectDisk product range is segmented into the following editions:
- PerfectDisk 11 Professional for workstations, laptops and standalone PCs running Windows 7, Windows Vista, and Windows XP Provides flexibility, control, and automation with its patented Advanced SMARTPlacement optimization technology.
- PerfectDisk 11 Server features patented Advanced SMARTPlacement optimization technology and the industry’s most complete free space consolidation to boost write performance.
- PerfectDisk 11 vSphere Bundle improves vSphere performance (VscsiStats) and is a complete solution that optimizes the physical host, guest machines, and storage solution to eliminate I/O throughput and I/O latency bottlenecks. This includes the optimization of both fat and thin provisioned virtual storage on both local and external RAID / SAN solutions.
- PerfectDisk 11 Hyper-V Bundle is a complete solution that is proven to increase I/O throughput, and decrease I/O request latency by 35% or more. PerfectDisk 11 Hyper-V enables high performance for virtual machines and maximizes the performance of storage solutions.
- PerfectDisk 11 Exchange automates the compaction and defragmentation of Exchange data stores to restore performance and disk space. It leverages all the capabilities of PerfectDisk 11 Server and supports Exchange Server 2010, 2007 and 2003.[9]
- PerfectDisk 11 Enterprise Console installs, deploys, configures, manages and reports on PerfectDisk 11 across computers, servers and virtual environments. PerfectDisk 11 Enterprise console also has the ability to customize up to 12 alerts on fragmentation of drives across the enterprise and allows customization of defragmentation schedules and virtual environments from a single location.
- PerfectDisk 11 Home Premium provides automatic background defragmentation, customizable scheduling options, patented file placement technology and boot time system file defragmentation. PerfectDisk 11 Home Premium is Microsoft certified for Windows 7.
- PerfectDisk 11 Windows Home Server eliminates WHS fragmentation, maximizes streaming media performance, reduces back up times, has seamless integration with the WHS Console and improves Anti-Virus performance.
- PerfectDisk 11 VMware Workstation Bundle is a host based license scheme with unlimited guests. It is a VMware Technical Alliance Partner solution providing dramatic performance improvements and eliminating Host and Guest I/O bottlenecks. PerfectDisk 11 VMware Workstation Bundle automates shrinking of virtual disks, re-indexing of virtual disks and automatic background optimization w/VIA Tech.
See also
References
- ^ PerfectDisk wins PC Magazine Editors' Choice, Windows IT Pro Readers' Choice, Redmond Magazine Readers' Choice, Download.com's, About.com's and CHIPS Magazine's (Germany) 5-star awards, and Vector Users' Choice (Japan's largest download site) Award; see also Editor's Choice, PC Magazine May 24, 2005, 2004 and 2002; and Windows IT Pro Magazine, Cover Story: Readers' Choice Awards, Sept 2006 [1]
- ^ "Where Is All The Vista Software?" PC Magazine Feb 2007
- ^ US Patent number 5,398,142. Filing date: May 31, 1989. Issue date: Mar 14, 1995 [2]
- ^ Microsoft Windows Defrag and Diskeeper use several disk passes
- ^ The Backup Book: Disaster Recovery from Desktop to Data Center by Dorian J. Cougias, E. L. Heiberger, Karsten Koop - Schaser-Vartan Books 2003 (ISBN 0-972903-909)
- ^ "Whats-new-PD11-defrag". Perfectdisk.com. http://www.perfectdisk.com/whats-new. Retrieved November 9, 2010.
- ^ Metadata defrag introduced in 1999
- ^ "SMARTPlacement" Patent number 5,398,142
- ^ "Storage". Windowsitpro.com. August 29, 2006. http://www.windowsitpro.com/Article/ArticleID/92699/92699.html. Retrieved November 9, 2010.
External links