Scratch disk hell.

[JamesOtwo]

Ok, here goes, the story of my scratch disk hell...

I'm running Photoshop 5.5 on a Mac with OS 9. I've got about 500mb memory free, virtual memory is off, and the desktop wallpaper is grey (they said be descriptive)

I don't usually work on images any bigger than about 40mb in size.

Up until recently I've had a good relationship with my Mac, we agreed on things, never argued, it was always reliable, obedient and punctual.

But it's started going off the rails, being disagreable, stubborn and often obnoxious.

The problems are with the scratch disks. I'll work for 20 minutes and then the scratch disk will just cram up. I'm forced to 'purge' the scratch disk after almost every operation, whether it be 'enlarge image' or a filter or whatever.

This has never really been a problem. I've cleared all unneccesary files off the hard disk, bulky image files, un-used applications etc, and still the problem persists.

Please help me, if these problems continue, I may have to resort to a trial separation, or even a divorce, I just can't take the feelings of resentment I'm getting from my Mac.

 

[jimoblak]

2 ideas - neither may help, but why not try?

1) Why is virtual memory off? Virtual memory is essentially a scratch disk for the OS. The only time one should disable virtual memory is when they have an application that requires fast RAM (ex: video/audio editing) and passing junk to the hard drive's virtual memory is too slow.

2) try defragmenting your drive. With all the gaps from the unnecessary files that were recently deleted, your hard drive is swiss cheese. Hard drives prefer to be cheddar. (I like metaphors too).

 

[SPYDERIX]

LOL Nice Analogy jimoblak

 

[mscallisto]

I thought it was a Simile, but whatever it is I'll probably use it!!

 

[HobbitK]

James,
We use PC's not MAC, so this answer mat be way off the mark(I know, all you graphic artists are shaking your heads in disgust). But here are some facts as i understand them.
The OS uses the primary partition as its virtual memory space, while Photoshop has an extreme desire of its own partition or better yet seperate harddrive for its scratchdisk (it is kinda like my kids, sometimes it does not play well with others)!
We resolved this issue on our PC's by using a partition magic utility, and setting up a 5 gig partition (drive letter becomes "D", and "C" is that much smaller). Then in Photoshop, we assigned "D" as its scratchdisk. Problem resolved. Analogy would be sending a misbehaving child into its room, to play alone, while all the others continue to play together and share all they have.
When photoshop starts running slow, it is very simple to dump all the junk photoshop puts on "D", and just defrag that small partition.
I do not know if there is a utility like this available for Mac, but if there is, you will NOT lose any files or anything, providing that your HD is large enough to support a partition of that size.
HTH
Michael

 

[twitchosx]

Hmm... nasty little problem. Its mostly not the Mac's fault. If it just started happening, it could be one or several of many things. Your HD could be messing up. Photoshop may not be understanding somethign correctly or your OS could be goofed up and not allowing the application to understand the scatch amount you have set. If you have more than one HD, be sure to go into your Photoshop Prefs and under Scratch Disks, make the secondary scratch disk your other drive. Also, turn on virtual memory and allocate about 250 mb of virtual memory. You might also try defragging. I have NEVER defragged my Mac.. either my old G3 300 or my newer Dual 800 and I am on a daily basis adding things and deleting things. If defragging on a Mac was as important as defragging on a PC you would know about doing that often like on a PC but I have found that defragging on the Mac isnt something that you need to do very much if at all but it MIGHT help in your situation.

 

[jimoblak]

The benefits (or lack of) defragging in OSX has been debated a lot. Most believe that the *nix filesystem does not really require much defragging.

OS9 and earlier can definitely make use of a regular defrag.

Regarding adding/partitioning a drive to act as a scratchdisk: I recommend a second physical drive.

Expect heavy use of caching to wear out a drive - - A second physical drive gives life to your main system drive.

A partitioned drive will also be slightly slower in access/seek times compared to a dedicated separate drive (hopping back and forth from temp cache to the system/program area.

I use external USB2/firewire drives for this.

- - picklefish - -