Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!uwm.edu!zaphod.mps.ohio-state.edu!mips!apple!mattd
From: mattd@Apple.COM (Matt Deatherage)
Newsgroups: comp.sys.apple2
Subject: Re: Copying SYSTEM DISK to /ram5
Message-ID: <42636@apple.Apple.COM>
Date: 4 Jul 90 22:44:02 GMT
References: <4862@darkstar.ucsc.edu> <3793@rex.cs.tulane.edu>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 54

In article <3793@rex.cs.tulane.edu> lang@rex.cs.tulane.edu (Raymond Lang) writes:
>I use 1 meg out of 3 as a ram disk, copy the system disk (5.02), add
>some DAs to the folder that won't fit on the disk, and then boot from it.
>What I _don't_ do is select Shut Down from the Finder when the Ramdisk
>is ready. I read here, on GEnie, and have experienced for myself problems
>with the Finder's Shut Down option.
>
Would you care to repeat some of those reasons?  Shut down in the Finder simply
ejects all the disks, shuts down the Desk Manager and calls OSShutDown, which
is a GS/OS routine.  Nothing funny here.

>After I've copied everything to Ram5, I use the control panel to change
>the startup slot to Ram, come back to the desktop, and then just press
>the ol' Open-Apple/Control/Reset. Works like a charm.
>
>So my suggestion to the people who are having problems doing this is
>to _stop_ using the Finder's 'Shut Down' option and just do a three
>key reboot.
>
This is not good.  People need to get in the habit of shutting down the system
without using the reset key.  If people won't shut down the system, it will
make it hard for us to add system-wide enhancements.  For example, maybe
someday we'd like to change the Finder so it uses a system-maintained desktop
database.  This would let it know where applications are without requiring you
to edit icon files.  Unfortunately, that means that when application files
move around, the desktop database would have to be updated.  To do so on disk
would be unacceptably slow; doing it in memory and only flushing to disk on
shut down or OS switching would be OK -- unless you do cold reboots and lose
all the information in the database.

Also, OSShutDown sends a Driver_Shutdown message to all the drivers, which
gives them a chance to save information not yet flushed to disk, disable
interrupt sources, and in general make things safe and sane.  Using the reset
key messes this up also.

Not to mention that you could corrupt any files the Finder just happens to have
open, or that desk accessories or INITs might currently be recording to, and
that not all file systems can recover from this as well as ProDOS can, or not
to mention that people who've installed procedures that get called on shutdown
get completely bypassed and don't get a chance to perform their tasks, and...
well, you get the picture.

If there's a problem with RAM disks and shutting down, I want to hear about it.
Globally recommending not shutting down is not wise, though.

>Ray
>lang@rex.cs.tulane.edu

-- 
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Matt Deatherage, Apple Computer, Inc. | "The opinions represented here are
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