Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!vax1.physics.oxford.ac.UK!MACALLSTR From: MACALLSTR@vax1.physics.oxford.ac.UK Newsgroups: comp.os.vms Subject: Disk defragmenters. Message-ID: <8806282211.AA01437@ucbvax.Berkeley.EDU> Date: 28 Jun 88 22:12:23 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 13 X-Unparsable-Date: 16-JUN-1988 14:54:18 GMT +01:00 While disk defragmenters may only produce dramatic performance improvements on very badly fragmented disks ( usually disks with little free space ) for individual applications, you will a notice drop in BACKUP time after the disk has been defragmented. I have tried DISKEEPER and RABBIT-7 and am using RABBIT-7 mainly because at the time the decision was made ( about a year ago ) RABBIT-7 gave more flexibility. Anyone using disk defragmenting packages ought to be aware of what the package is doing to the arrangement of files on the disk ; free space may be concentrated in one chunk at the beginning/end/somewhere in between of the disk or it may be divided into several separate chunks distributed over the disk. You must discover which formula suits your system : do you have many small/medium/large files or does the disk contain several large database files for example? John