You are here

HOW TO CRASH HARD DISKS AND SYSTEM SOFTWARE WITHOUT REALLY TRYING. (For people who may have to take care of their own Mac.)


Brian Pankuch

Note: This article was scanned using OCR from the Fall 1992 CCCE Newsletter. Please contact us if you identify any OCR errors.

          Actually the idea was to minimize problems with hard disks. I've been thinking for some time that I need a more effective way of protecting my work than backing up to a diskette. I'm conscientious about backing up big projects, but I have a lot of small things I do often and don't have a special diskette to back up to. With over 200 M on my system, I'm just not going to back the whole thing up on diskettes, nor am I going to set up a filing system to find a specific diskette (out of 200 or more) for a small piece of work. The easiest solution seemed to be to get a 88 M removable Sysquest cartridge and drive, about $500 for both. This would also give me a backup hard disk. Additional 88 M cartridges are about $95, so you really have backup limited only by your pocketbook.

          On the other hand I've been using computers for quite awhile and have never had a hard disk problem. I've heard of plenty, but I've got the best quality hard disks and have been lucky. Also I like a bargain and I got an outstanding mail offer from Symantec for their Norton Utilities and MORE, a presentation manager, for about 85% off the list price. Symantec combined the best of Norton and their own SUM II utilities to do preventive medicine on hard disks and to recover lost files on a crashed disk. Total price was $95. This didn't give me the same protection as a spare hard disk, but it should lessen the chances of problems. If problems do occur I have a way of recovering files. It is cheaper and probably easier than backing up 88 M often.

          So I bought the Symantec software rather than the hardware. I set it up on my Quadra 700. Installation of Norton was easy. To use some of the utilities such as Disk Doctor was straight forward. The utility chugged through the hard disk and found a number of anomalies- some programmers amuse themselves by giving the date of completion of a program 1909 or 2040. Harmless but the Norton disk doctor fixed these and other anomalies.

          Next day I decided to use Speed Disk, which optimizes the disk. Files on your disk are usually written to one physical area on the disk at first. As the file changes size the original space set aside may not be large enough. The part that doesn't fit is put into another physical location on the disk. After many repetitions your disk is fragmented. Parts of the same file are all over the disk. Reading the file from the disk will take longer since the reading head has to find each part. This also results in a lot of head movement with additional wear. Speed Disk will put files back into contiguous areas. It will also place files that don't change much in the beginning of the disk and the often modified files at the end where they can grow. This should save a lot of wear on the hard drive mechanism and put off eventual failure. My drive has an estimated mean time between failure of over 22 years, but only a 5 year warranty.

          To use Speed Disk you have to run the utility from a disk other than the disk you are checking. Symantec thoughtfully supplied a boot disk for this purpose. I restart my Quadra with this disk, and it comes up in Speed Disk and tells me there is not enough memory. The Quadra has 20 M of RAM and access to another 300 M of virtual memory! I can't get at the disk to check because it won't let me out of Speed Disk. So I try to restart and the entire system crashes. I try everything I can think of and finally replacing the entire system file lets me restart the computer. I run Disk Doctor and it says everything is great, I restart just to see if it will, and again the whole system crashes. After about 6 hours I learn more about disk utilities than I really want to know.

          My problems were first, the Speed Disk program didn't have enough memory set aside for itself, my Quadra had plenty, but programs aren't smart enough to go grab some. You change allotted memory by selecting the utility, then selecting Get Info from the file menu (Command 1). When the Get Info window opens change the 600 K allotted to at least 1 000 K. I changed mine to 14,000 K since I have a lot of memory - the more memory set aside the faster Speed Disk will optimize your hard disk (it can take hours). You can't change the allotted memory on the boot disk while you are using it because you can't get at the file. You also can't change this setting while you're using the program (this is true for all programs). Make the change while this diskette is not the startup disk.

The second problem is more general. Most of us use many utility programs (INITs) -clocks, calculators, etc., on the screen. I get a lot, and I test a lot. These utilities can change the System software that runs the computer. They frequently take over the same parts of memory. If not well designed they wipe out part of the system memory when they collide. After taking out many of these INITs that I no longer needed, and replacing and updating the system, everything works fine.

          As an experiment, I ran Speed Disk on a Mac IIX running System 6.07 - it did exactly the same thing. The SAM virus utility (also made by Symantec) was causing the problem.

          Speed Disk ran fine on both machines after removing the problem INITS. This all happened on a weekend so Symantec teleplhone help was not available. I called even though I had Speed Disk working. As a general preventative Symantec suggested prefixing the Norton file name with a 'z' so it loads last and lessens the chances of problems with other utilities.

          MORE I've only started to use MORE, but as I mentioned previously the balloon help under the Mac System 7 makes exploring a lot easier and more interesting. Even in a well-designed program exploring is sometimes quite complicated. I find using balloon help much faster than trying to look through the 5 books (2 books and 3 booklets to be ore precise) included with MORE. Also if I do need to look up additional detail in the reference manual, balloon help gives me the name of what I'm looking at. This is an enormous time saver in a complicated program.

          This has little to do with chemistry, but tax preparation packages can be time savers. I used MaclnTax two years ago and found it very helpful. All the tax forms come up on the screen with help available, and act like spreadsheets. If you add or subtract something, all amounts affected are updated. If you're 3 or 4 forms deep this can save a lot of drudgery. When it works you can automatically move names of banks, charities, and other categories to next years form. Last year ChipSoft, a DOS oriented company, took over MaclnTax. The new program was so bad I had to return it. Considering I didn't return Norton Utilities that's bad. I hope this year will be better. Less time for taxes
may give you more time for students.

09/01/92 to 09/05/92