Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!uwmcsd1!ig!agate!ucbvax!CORY.BERKELEY.EDU!dillon
From: dillon@CORY.BERKELEY.EDU (Matt Dillon)
Newsgroups: comp.sys.amiga
Subject: Re: Amiga floppies (was: Re: Blitter vs. 80386)
Message-ID: <8808272311.AA03507@cory.Berkeley.EDU>
Date: 27 Aug 88 23:11:41 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 27

:blocks, for the worst case UNIX is faster than best case AmigaDOS for up
:to 32 files (it takes 2 disk accesses to verify a filename in AMigaDOS),
:and just as fast for up to 64 files. I haven't figured in the effect of
:hash table collisions in AmigaDOS, and on average you're going to have
:half the number of accesses in UNIX.
:> Of course, Unix DOES have disk caching, while MSDOS doesn't...
:
:And AmigaDOS doesn't. Even with FACC AmigaDOS doesn't have preferential
:caching of directory entries.

	Actually, the FFS does.  The old file system did too but it was
really stupid caching.  The FFS is *much* better at it.  Still not as fast
as UNIX but that is only because UNIX directories, being files, can be
accessed sequentially very quickly.  When you get down to openning a specific
file, such as would be done in a large CAD system or when searching the PATH,
the FFS is *much* faster!

:On MS-DOS, the whole file entry is stored in the directory, so there are
:even fewer slots per directory entry and MS-DOS has worse directory-search
:behaviour than UNIX.
:
:I've run MS-DOS and UNIX on the same hardware. UNIX is noticably faster.
:I'd like to make the same comparison on a 2500UX some time.

	MS-DOS combines the worse of both worlds.

					-Matt