Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!shadooby!samsung!uunet!loft386!DSUVAX!ghelmer
From: ghelmer@DSUVAX.uucp (Guy Helmer)
Newsgroups: comp.os.minix
Subject: Re: How to use a hard disk with Minix
Keywords: hard disk
Message-ID: <1989Nov29.142807.3944@DSUVAX.uucp>
Date: 29 Nov 89 14:28:07 GMT
References: <312@trux.UUCP>
Organization: Dakota State University
Lines: 27

In article <312@trux.UUCP>, car@trux.UUCP (Chris Rende) writes:
> ...
> Observation:
> I can see the head positioning mechanism moving on the HD while the disk is
> operating. Minix seems to do alot of seeks back to the start of the file
> system, cyl 0, super block, or whatever. While doing a "cat somefile" the
> head seeks to a block from somefile, returns to the start of the disk, seeks
> to the next block of somefile, returns to the start of the disk, etc...
> Why does the head keep returning "home"? How can this be reduced?

Strange behavior.  "cat" shouldn't be updating the superblock (should
it?), so MINIX shouldn't be going back there.  MINIX should have the
inode in-core, from what I see in the source code, so it shouldn't be
messing with the inodes.  Either your file is really fragmented across
the disk, your file is bigger than 9 blocks (requiring single or
double indirect access to get zone numbers for the file), or MINIX is
doing something I can't figure out yet.
 
> Christopher A. Rende           Central Cartage (Nixdorf/Pyramid/SysVR2/BSD4.3)
> uunet!edsews!rphroy!trux!car   Multics,DTSS,Unix,Shortwave,Scanners,StarTrek
>  trux!car@uunet.uu.net         Minix,PC/XT,Mac+,TRS-80 Model I,1802 ELF


-- 

 Guy Helmer                                           ghelmer@dsuvax.uucp
 Dakota State University Computing Services           helmer@sdnet.bitnet