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Important caveats
Authored by: strebe on Feb 21, '04 01:58:18AM

After considerable experimentation I have to conclude that it's not wise to put your swap files or OS X applications on a separate volume, and even /Users might be problematic.

The reason swap files on other volumes fails sometimes is that there is no mechanism in place to guarantee that the volume has mounted at the time OS X sets up the swap directory. Volumes are mounted by a separate, parallel process from the process that initializes the virtual memory. In order for the method in this hint to function properly, code needs to be added to detect that the process for mounting volumes has terminated before proceeding with the initialization of virtual memory. I don't know how to do that.

The reason /Applications can't be on a separate volume is that some Apple applications blindly walk up the directory path looking for specific cousin directories. They fail once they rise above the /Applications directory because they end up in /Volumes instead of /.

There are probably other obscure ways that this hint causes failures. Putting /Users on another volume would seem safe enough -- heck, it's just user data -- but I discovered that using an alias (symbolic link) of /Users/.../Library to place it on another volume causes the dock to fail to save its state. That's not the same as a different mount point, but it's a similar concept and it causes failures. Therefore I'm guessing other stumbling blocks remain to be found.

Hence I've mostly given up trying to defeat Apple's manic insistence on dumping everything on one volume. I still have to do something, though, because of the 8GB limit on the boot volume in early G3 systems. I have, regrettably, set up the /Users/.../... directories such that they are all aliases onto an auxiliary volume, but leaving /Users/.../Library/ on the boot volume. Hence Music, Pictures, Documents, etc. are all on the auxiliary volume but the user directory itself along with the /Library directory within it stays on the boot volume. In this way I avoid stuffing the boot volume while minimizing the chances of bizarre failures.



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Important caveats
Authored by: lerici on Jun 17, '04 12:59:29AM

You can "fix" the synchronization problems by editing the file /etc/rc.boot. Apple has fixed up their startup scripts so that there isn't any synchronization problem. IN fact they ensure they mount the disk within this script before doing anything at all. This is fairly typical in any UNIX environment. I have actually created a separate /var partition (UFS) and mounted it in this manner. THIS does work. Given the nature of HFS+ and the problems inherent with that file system a setup which includes only two partitions var and / make sense. The constantly changing files (and the swap files) would reside on a separate partition protecting the root partition and its critical databases from catastrophe.

As far as the rest of your commentary. Yes, it is true, some installations choke if /Applications is on a separate partition. Typically these are application updates rather than installs. Apple need only include an option to overwrite the app instead of just upgrade and I believe this problem would disappear. Unfortunately, you must often avail yourself of pacifist... or manually install the packages using pax etc. to resolve this. So far this has
not been a problem for me... of course the "vise" installers are a different story but over the last year or so they have improved significantly and seem to readily handle a multiple partition set up.



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Simple workaround for installing iTunes upgrades
Authored by: DavidVH on Jun 22, '04 01:17:48PM
With iTunes on my Apps partition, Apple's iTunes 4.5 and 4.6 updaters (via Software Update) did not actually update the iTunes application. And after the failure of Software Update, downloading the new version of iTunes from Apple and running the installer was equally ineffective, even though it ran without giving any error message. I found a fairly easy solution, though:
  1. Delete the "iTunes4.pkg" file from /Library/Receipts

  2. Download the new version of iTunes at:
    http://www.apple.com/support/downloads/itunes.html

  3. Run the iTunes installer.

Voilà!

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Clarification to workaround for installing iTunes updates across partitions
Authored by: DavidVH on Nov 10, '04 10:27:44PM
In case you're wondering about the previous comment: Yes, you have to download the entire new version of iTunes, not an updater. The download address has changed, too; use one of these instead:

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Ensuring drives/partitions are mounted
Authored by: blakers on Jun 17, '04 03:06:38PM
 > there is no mechanism in place to guarantee that the volume has
 > mounted at the time OS X sets up the swap directory. Volumes are
 > mounted by a separate, parallel process from the process that
 > initializes the virtual memory. In order for the method in this hint to
 > function properly, code needs to be added to detect that the process
 > for mounting volumes has terminated before proceeding with the
 > initialization of virtual memory. I don't know how to do that.
here's how, per a comment from Apple in a 'discussion' i'd had on the darwin-kernel list ...
From: Dan Markarian 
To: Darwin Kernel List 
Subject: Re: ?? how to get SystemStarter/diskarbitrationd to wait for drives to mount ??
Date-Sent: Friday, June 11, 2004 8:17 AM -0700


> There are two ways to have it mount at boot.  The first one, also the
> ideal one, is unfortunately not working in 10.3.x due to an oversight
> on our part.  I mention it only for future reference.  It would be to
> list the volume in question by UUID in /etc/fstab along with the "auto"
> option.  This would override any default.

re: "future reference" ... i assume you mean that fstab in not currently being used/checked, not that it currently/default is simply empty.  yes?

> My alternative would be to create the preference file in
> /Library/Preferences/SystemConfiguration/com.apple.DiskArbitration.diskarbitrationd.plist with this:


<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist SYSTEM "file://localhost/System/Library/DTDs/PropertyList.dtd">
<plist version="0.9">
   <dict>
      <key>DAMountDeferExternal</key>
      <false/>
   </dict>
</plist>
the mod to "com.apple.DiskArbitration.diskarbitrationd.plist", i can verify on Panther 10.3.4, works perfectly.

richard

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Ensuring drives/partitions are mounted
Authored by: bluehz on Jun 18, '04 07:19:00AM

I have been using the /etc/fstab method for over a year - through several OS X upgrades and I can verify that it is STILL working in the current 10.3.4. fstab - is still viable in 10.3.4.



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