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tezza
April 11th, 2009, 05:30 PM
A question regarding Apple hard drives of the late '80/early 90s vintage.

Did they ever need defragging and if not, why not? I haven't explored OS 6 or 7 thoughroughly yet, but defrag doesn't seem an option? Or at least easily performed?

Maybe I just haven't explored it thoughroughly?

Tez

NeXT
April 11th, 2009, 06:24 PM
I think the closest thing I have ever seen a mac come close to in the way of a defrag was rebuilding the desktop.
I know there were those odd defrag tools but either they were the desktop rebuild in disguise or HFS stands up really well to not fragmenting.

Unknown_K
April 11th, 2009, 10:59 PM
There was a program that defragged hard drives meant for video only, forget the name. I think Norton for mac did defragment the HD if you booted from the CD 1st. To be honest I never realy had to defragment a mac HD on my old system 6,7,8,9 systems. Mac OSX defrags when you are done installing updates.

arjoll
April 12th, 2009, 03:51 AM
Yes, I'm sure Norton Utilities for Mac had a defrag tool. I think we used to do it occasionally on the Mac Portables (System 7) when I was working for the local office of one of the (then) 'big six' accounting firms.

niteshooter
April 28th, 2009, 04:37 PM
I used to use Speed Disk which was part of Norton utilities but that was on a Mac used as a FirstClass server which is rough on hard drives.

Otherwise not really, I'd be more concerned about the noises those old drives might be making since that could be an indication that they are about to fail.

scorch
May 8th, 2009, 11:50 AM
I think the real issue is whether defragging is ever truly necessary? To me defragging, if done at all, should be an automatic OS function based on heuristic methods during storing (writing) files to the drive. To task the user with this operation is like saying you must personally change your spark plugs in order to operate your car. In fact, I think that defragging could be eliminated altogether with smarter file allocation techniques. This is especially true on todays HUGE drives where you potentially have lots of "head room" to work with.

A misunderstanding that's not widely reported is that, defragging NEVER fixes any drive errors! In fact, if you suspect you have drive errors you should definitely avoid defragging. Defrag purports to speed up certain types of disk accesses, but there is also risk involved. During a defrag, files are physically relocated on the disk surface, and the FAT (file allocation tables) updated appropriately. If there is any initial discrepancy between the physical file allocation and the FAT to start with, and you defrag, then you've likely turned a small problem into a much bigger one! Also if you have any kind of intermittent power glitch or outage during the defrag process, then your hard drive will be left in an indeterminate state.

I have 3 main systems plus a laptop, and have never defragged any of them. However, I do surface scan in rare cases where a read or write error occurs. In days of old when drives were more limited as to transfer speed, disk space, and buffer size, defragging may have had some validity, but I'm not convinced it is important today, especially given the risks. I know this post is not timely, nor does it even address tezza's question, but as a retired engineer, I have opinions about nearly everything and all the time in the world to share them :D

Unknown_K
May 8th, 2009, 12:27 PM
Defragiing is just for speed, not for file errors. With new drives being very speedy and having large caches it is not as needed as in the old days of slow drives with small cache.

The application I used defragging on was video capture for late 68K and early PPC mac systems. It was hard back then for the drive to keep up with captured video and having to jump all over the drive would drop frames.

Dreamcast270mhz
May 9th, 2009, 06:31 AM
The only filesystems needing defrags really are the FAT family, NTFS, and some older UNIX filesystems.

swaaye
June 4th, 2009, 03:01 PM
I'm with scorch on this. I think fragmentation and defragmentation are concepts that are riddled with rumors and urban myths. PC users really can get all caught up on it when it really only has a tangible impact in some rare situations.

I too remember a Norton defrag for older Macs.