why separate filesystems?

[Vernon Schryver]

In article <1990Aug24.215127.766 at ico.isc.com>, rcd at ico.isc.com (Dick Dunn) writes:
>      ...   Otherwise you'll
> spend your time seeking back and forth across the unallocated wasteland at
> the end of the first file system to get to the second....


This is more true in under-designed file systems like that in System V.
Many file systems which started with bit-map allocation mechanisms spread
the unalloated wasteland throughout the allocated rubble.  Consider BSD FFS
cylinder groups or the file system of the 1960's Project Genie.

This is just a nit.  I agree with Dick.  Consider the popularity of logical
volumes, where several physical extents are pasted together into the
illusion of a single large file system.  Such games were vital for UNIX
files larger than 2GB (or 4GB if your u_offset is unsigned) before 2GB
drives became cheap.


Vernon Schryver
vjs at calcite.uucp