Benjamin Scott <[EMAIL PROTECTED]> wrote:
>>> Does anyone know of any unbiased and current analysis of this issue? Well, no, and to be honest, my opinions are quite biased. The MS-DOS filesystem design flaws, with respect to fragmentation, are well-known and understood. (O)VMS's filesystem suffered from similar problems. Two of the primary architects of (O)VMS work for Microsoft now, and one of them - Dave Cutler - was the primary architect of Windows NT. The NT (and NTFS) design is very similar in many respects to (O)VMS, and suffers from the same fragmentation issues. For many years, Microsoft was unwilling to admit that, but eventually the truth, and Diskeeper, came out. The BSD filesystem used by many flavours of UNIX, including ULTRIX, OSF1/Digital UNIX/Tru64 UNIX, SunOS, IBM AIX, HP-UX, et al., tends to minimize fragmentation. There is _some_, but it is minimal, about 1-2% or so. I won't waste list bandwidth explaining why, because there are a lot of interesting papers online about it. We had one of the primary designers give a talk here one time; she'd been researching a way to improve upon it, and was discussing her research, putting up all kinds of performance graphs, etc., etc. Went on for 45+ minutes. At the end, she put down her pointer, crossed her arms, looked at us and said, "And after all THAT [~2 years of research], we still couldn't find a better way!". Kind of stunning, but her honesty was refreshing. The EXT2 filesystem, I believe, is based on many of the design principles as the BSD UNIX Filesystem (ufs) mentioned above, and as such, its exposure to fragmentation problems is minimal. The basic concept is that the OS's filesystem code works in the background to keep the files contiguous as possible, commensurate with good overall performance. However, I'm sure there are other experts on the list who can correct me on that and explain it all a lot better than I. HTH, Bayard ***************************************************************** To unsubscribe from this list, send mail to [EMAIL PROTECTED] with the text 'unsubscribe gnhlug' in the message body. *****************************************************************
