From: sadkins@bigbird.cs.ohiou.edu (Scott W. Adkins)
Newsgroups: alt.uu.comp.os.linux.questions
Subject: Re: SLS distribution question
Date: 20 Jan 93 13:51:22 GMT
Organization: Ohio University CS Dept., Athens

In article <1993Jan19.123922.7763@cs.ruu.nl> hubbers@cs.ruu.nl (Jan-Willem Hubbers) writes:
>
>>Why do you want all those partitions anyway?   [Why not put them all on
>>   one partition...]
>
>There are several reasons NOT to to do this.
>1) The efs is still considered to be an alpha-release. It seems to run
>	 pretty stable, but still... I just like a thoroughly reliable file
>	 sytem better than making many backups.
>2) The minix fs is faster
>3) A single mishap can corrupt ALL of your data if it resides on a
>	 single partition.
>4) The efs fragments more.
>5) Although it would be nice to have filenames longer than 14 char's,
>   not everybody needs them.
>7) For those with less than 16MB internal mem: a swap partition is
>   faster than a swap file.

Yes, but this is not the *real* reason why people use multiple partitions.
Here are some reasons:

1)  Yes, there may be a quota system for user accounts, but are also going
    to put a quota system /tmp and /usr/tmp?  You would have to in order to
    prevent users from using up all the remaining disk space and crashing
    the system?

2)  Ok, lets say that you don't worry about the users and the temporary
    directories.  You still have to worry about news/mail/editor/etc 
    programs writing to those direcotories and maybe other directories 
    and filling up the remaining space.

The above two reasons is why /tmp is usually mounted onto its own partition,
as well as /usr/tmp (but not as often, since /usr is instead mounted on its
own partition), and /usr/spool is usually mounted on its own partition (you
really *do* have to worry about to much mail and news coming into your system
if you choose to support them in certain ways...)

3)  Ok, what about the times that you want to build special or new application
    programs or systems?  It is usually nice to maybe have a partition 
    dedicated to such things... for instance, what if you were working with
    X11R5 and you currently have X11R4 on the system?  Well, you could put
    the X11R5 on a partition and just mount it on top of the X11R4 directory
    and see if things work... (this is a really really *bad* example, but
    you at least see what it is that I am saying).  You can then umount it
    and leave it unmounted when you are not working on it.  (Call this a 
    development partition).  This is probably safer than just turning off
    directory permissions to everybody but root...

4)  Related to something in the #3 above... if you are working on something
    important, you would hate to see the data get corrupted on the whole 
    partition because of a glitch caused by one little program...  I think
    this was mentioned in the above original reasons.

5)  Another reason to have partitions, and a little more used, is that you
    might want to backup some or all of your programs to another partition.
    In case something happens to, let us say, the root partition, then you
    still have a backup root partition that you can mount until you get the
    original problem fixed.  

6)  Again related to the reason above... let us say you just updated to a
    newer version of the operating system.  You of course backed up everything
    to tape or disk (if you didn't, you will die a horrible death).  But 
    wouldn't it be nice to keep the old system and files on another partition
    to readily mount and set up in case the new system has too many bugs or
    problems?

7)  For my last reason, and one that also gets used a lot... if you want to
    have multiple file systems, then you have no choice but to have more
    than one partition.  But you can see this one....

Well, anyway, these are some of the reasons that get used for having multiple
partitions.  It is very useful and can server to protect your system from the
normal wear and tear (and corrosion and blah blah blah) of normal every day
use.  If you do not do this, you are asking for trouble (no matter what it is)
sometime down the road.

I hope this helps.

By the way, I currently have a 120 meg allocated to the Linux system.  It
is split up 62 meg for the root file system, 32 meg for the /home file
system (for the user accounts), and 26 meg for the /tmp directory.

Scott.
sadkins@ohiou.edu
-- 
         Scott W. Adkins           Internet: sadkins@ohiou.edu
         ~~~~~~~~~~~~~~~                     ak323@cleveland.freenet.edu
    Ohio University of Athens        Bitnet: adkins@ouaccvma.bitnet
Newsgroups: alt.uu.comp.os.linux.questions