This document has styles in it. You may view them with a text editor such as Tex-Edit by Tom Bender or Style (1.2.1 or later) by Marco Piovanelli, or Apple SimpleText by Tom Dowdy.
• SHAREWARE - US$10
◊ This program is distributed as Shareware: if you use it regularly you should pay the author. Preferred methods are cash (US$) or international money order. If you do not feel like using these methods, sending an equivalent sum with your local currency will do.
Collecting international cheques is VERY expensive: this means that banks charge some $15 to $30. Thus, DO NOT send cheques, please.
◊ NOTE: Getting a note, a postcard or anything else is a lot better than getting nothing. I would like to know how far this program has gone, so remember that you can do something nice even if you do not have a couple of $ to spare.
• GENERAL INFO
◊ Any hard disk may be split into multiple disks, called partitions. Unfortunately, Apple HD SC Setup (the application Apple provides on System disks) will not let you create more than one Macintosh partition. SetupPartitions lets you overcome this limitation. How? Launch Apple HD SC Setup; the latest version is 7.3.1, included inside the System Update 3.0:
I know that System 7.5 includes Apple HD SC Setup 7.3.2; I do not know whether it will be freely available.
Create two or more partitions, as you would normally do, choosing the type “Scratch”. Quit Apple HD SC Setup, then launch SetupPartitions. Select the hard disk you just partitioned; SetupPartitions will transform the “Scratch” partitions into Macintosh HFS, MFS, or Apple // ProDOS partitions, at will. Nicely indeed, the System does not mount MFS partitions. If you succeed in mounting on the desktop a MFS partition, tell me how in the world you made it.
◊ SetupPartitions lets you use true, “hard” partitions (as opposed to “soft” partitions). If this sounds meaningless to you, do not worry: you can use SetupPartitions (and live comfortably) altogether.
◊ You can launch SetupPartitions multiple times in a networking environment, as well as from a locked disk (CD-ROMs are welcome; by the way, if this application is included on a CD it would be nice to send me a complimentary copy of it).
◊ SetupPartitions can only be used under System 6.0.4 or later; if you try to start it up under older versions of the System you will get an error message.
◊ A clever partitioning strategy lets you experience a storage gain:
Partition size (s) | File size | Actual disk space used
The shareware application ShowSizes by Jon Pugh <jonpugh@netcom.com> shows this fact quite well. Apple is aware of the fact that big partitions have lots of wasted space: reportedly, the codenamed Gershwin System release (System 8?) will not exhibit this behavior.
◊ Asynchronous I/O? SCSI Manager? What is it?
Async I/O means that the CPU (the microprocessor) says to your hard disk, tape drive, or any other device: “I want to read this file into memory”. The CPU continues working on other tasks, until the device says to the CPU: “The data transfer you asked for is complete”. Look at this scheme:
The File Manager supports asynchronous requests from applications since 1984. The problem is that the SCSI manager running on almost all Macs handles the async request exactly as it was a sync request. That is, the CPU has to sit down until the data transfer is complete.
The new SCSI Manager 4.3, present in the ROMs of the AV and PowerPC Macs, does support async I/O. Unfortunately, the old SCSI drivers tell the SCSI Manager to transfer data “the old way”. The new Apple SCSI driver inside Apple HD SC Setup, in theory, knows how to speak to the SCSI Manager 4.3, exploiting async I/O. In fact, I discovered that it does not. I wrote a quick & dirty application doing the following:
1) opens a window;
2) creates and opens a file on the startup disk; issues a 3 MB Write Asynchronous call; while the write action takes place, it draws random numbers into the window;
3) reads asynchronously the 3 MB just written; while the read action takes place, it draws random numbers into the window;
4) closes and deletes the file.
Guess what? For each I/O request (about 2 seconds) only one number is drawn in the window (Quadra 700 with the latest Apple driver). Again, the CPU has to sit down until the data transfer is complete. I obtained the same results on a PowerMac 6100.
Q. - I do not use Apple HD SC Setup to format my hard disks. Does my formatter support SCSI Manager 4.3?
A. - I do not know. Ask the software company selling the formatter.
Q. - Does the SCSI Manager 4.3 included inside System 7.5 run on all Macs or just the Quadras?
A. - I do not know. Interesting question, though.
Q. - Will Apple implement the SCSI Manager 4.3 so that runs on the older Mac models?
A. - I do not know. Ask Mr. Apple Computer, Inc.
Q. - My brand-new Mac has an IDE hard drive. Will SetupPartitions support IDE drives?
A. - NO.
Another useful piece of information: software running at interrupt time is forced to use async reads&writes, because sync system calls would not work (at interrupt time); networking software runs at interrupt time => networking software (FIle Sharing, etc.) uses async calls, so it should be more efficient, provided that the SCSI driver exploits the SCSI Manager 4.3.
◊ Apple hard disks usually come with a bit of unused disk space. This unused, empty space is the gray area you see in the “Custom” partitioning dialog in Apple HD SC Setup. The usual tip experts give is: backup the existing partition, remove it, then create a new one covering the entire disk; restore the previous contents. Since backup&restore is a time-consuming operation, you may want to exploit the unused disk space by creating a new scratch partition and using SetupPartitions.
• DISCLAIMER
◊ “No warranties at all, either express or implied…” “All trademarks are held by their respective owners…” and all that stuff.
This application should do no damage, but if it does then you will be on your own. Let me know of any bugs you run into, anyway.
• VERSION HISTORY:
◊ 1.0.4 - Native PowerPC code; updated the docs.
◊ 1.0.3 - Added Roberto Masera in the credits (I forgot this one); removed the resources mistakenly allowing drag&drop; now supports the standard Apple Events when running under System 7.
◊ 1.0.2 - Clarified the documentation; little fix in the registration code.
◊ 1.0.1 - Updated the documentation and a couple of alert boxes (clarified some issues); no code changes.
• THANKS TO…
◊ Federico Cavaglià, because he did not swear too much when his hard disk was wiped out by a preliminary version of SetupPartitions (he had to reformat).
◊ Edoardo Ciotti tested on his lowly Mac SE.
◊ Jeffrey Fritz, William M. Porter, and Dave Yost gave important user interface suggestions implemented in 1.0.1.
◊ Roberto Leonardi helped with the italian translation.
◊ Alessandro Levi Montalcini did not test much because he had not enough time (luckily indeed, because the very first version I sent him is the one that wiped out Cavaglià’s disk).
◊ Roberto Masera looked for the SCSI documentation on the Internet; SetupPartitions would have been really worse without the documentation he found for me.
• ENJOY YOURSELF,
and remember that more and more shareware authors are going commercial because they receive almost nothing. If you don’t pay for good shareware software today, you are likely to pay much more in the future for exactly the same features, plus a nifty package, a good manual, and perhaps a copy protection scheme or a serial number; you know you don’t need the package, or the copy protection, and undoubtedly you will not want to waste your time reading manuals.
To report errors, suggestions, or whatever, send e-mail to simula3@di.unito.it
