Photoshop failed to quit and is not responding

Question

I've had a nasty problem for the past few days that seems to be getting gradually worse. ie it now happens within a few minutes of openning Photoshop, whereas before it was happenning after an hour or two of working on an image....
At some point while working on a moderately complex .psd (roughly 70mb with some 15 layers) Photoshop hangs and Force Quit Applications tells me that Photoshop is not responding. I can't identify anything particular that i'm doing that triggers it.... i use a fairly wide variety of tools and filters and the hang doesn't seem to be triggered by anything specific.
I force Photoshop to quit, and it disappears from the Force Quit Application list. However, after quitting, I cannot open .psd or .jpg files from Bridge or from Finder. Raw files open up ok from Bridge into Camera Raw. And, when I try to shut down or restart my machine i get: " Logout has timed out - The application Photoshop failed to quit and is not responding." so the only way to restart is to force a shut down with the power button. After restarting the Mac Photoshop works ok again for a a while and then the problem happens again.
I have repaired my disk permissions and run Diskwarrior over both my Mac HD ad the external Firewire drive where all my images live - which didn't identify anything out or the ordinary.
Any thoughts on what else I can do to eliminate this problem would be v gratefully received
I am working on a Dual-Core Intel MacPro with 9GB memory, running OS 10.4.11 and Photoshop CS3 10.0.1 and Bridge CS3 2.1.1.9

Answer 1

Neil, just for reference the Cron script problem was fixed in 10.4.2 and should be run on boot if they haven't already. This doesn't mean that running cocktail occasionally to make sure doesn't have value or to run the maintance scripts early doesn't help (it wont hurt).
Nick
The 3 Gb limitation is a limitation of 32bit operating systems and software. Photoshop can't address (use) more than 3Gb regardless of how much you have free or installed. OSX 10.4 is kind of 64bit but not completly, it has the ability to remap memory so EACH program can use a max of 3Gb. so in your case with 5ish Gb used PS is using 3Gb, Safari is using a bit and the OS is prob using most of the rest.
Looking at what you posted the only two figures your really interested in is the Used and Free (which add up to approx 9Gb). The fact that the used number doesn't change from the several files open and the liquify filter opening indicates to me that it has already grabbed as much memory as it can( it's using 3Gb of the 5.52, the rest is the OS etc).
Simply put PS IS running out of memory. You can help this by putting the memory allocation in the PS preferences higher (the OS will use other areas of memory so it wont cause a problem) and make sure the scratch disk is set to a drive with plenty of space. But keep in mind the Liquify filter is VERY memory intensive so you may not be able to use it with lots of files open.
BRETT