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Tarandon · Posted: Sat Jan 12, 2002 11:29 am

Does anyone here know how to set up a Ram Drive? Or better yet know of an online site with a tutorial on how to do so? I have all this Ram and no way to exploit it right now. I was thinking to set up a ram drive and tell my cpu to use it instead of the hardrive for a swap file. Anywho, your help would be greatly appreciated.

Thanks

Loki · Posted: Sat Jan 12, 2002 11:36 am

Sorry - I might be wrong, but wouldn't it be easier just to allocate all of the RAM in Photoshop?

Tarandon · Posted: Sat Jan 12, 2002 11:54 am

no, computers only use ram to display the working section of the image all the rest of it is stored on the hard drive and accessed when you navigate the image. So, if one were to stored the unaccessed sections in a ram drive it would be like having the whole thing in ram instead of just a piece of it. Its way faster, trust me

Frost · Posted: Sat Jan 12, 2002 3:14 pm

"no, computers only use ram to display the working section of the image all the rest of it is stored on the hard drive and accessed when you navigate the image."

...and who might have told you that, sir?

[Shizo] · member Member # Joined: 22 Oct 1999 Posts: 3938

Ram drive would be an interesting experiment, but not worth the walk (for me at least). Unless you have some really slow HD and a lot of RAM which doesnt happen often.
I saw tutorial someplace.. should be easy to find on www.google.com

LoTekK · Posted: Sat Jan 12, 2002 10:28 pm

if you're working on very large images, it's certainly not worth it unless you have money to blow on about 10 gigs of RAM... come to think of it, i don't think any consumer system can handle that much RAM anyways... in addition, by allocating a lot to RAM, windows won't be able to access the RAM, and it'll end up writing lots to virtual memory, slowing things down anyways...

i'm with loki on this one...

frostfyre · Posted: Sun Jan 13, 2002 12:13 am

That's a very system specific question. Telling us your OS would help. I'm not sure its available on systems besides MacOS 9.x and earlier. On those systems, its just a matter of switching on RAM disk and rebooting. Its in the memory control panel. Good luck!

Tarandon · Posted: Sun Jan 13, 2002 2:14 pm

Alright cool, thanks for the help peeps.

Pat · Posted: Sun Jan 13, 2002 3:37 pm

Ok, set up a RAM disk on MacOS 9 to test the results for digital painting. Hardware: Stock G3/450 with 5400rpm IDE drive that sustains ~24 megs per second. Subjective results follow:

Test Parameters:
512 megs total, 128megs allocated to Photoshop and 200 megs allocated to a RAM disk partition. Doc size was 3000x2000 pixels, RGB.

Results:
I was able to contain the entire document in RAM. No physical disk activity whatsoever. I found painting to be somewhat faster, especially for quick hatching strokes. Previously, on my non-RAM disk setup, the drive would click after each miniscule stroke, and after a quick succesion of stokes there would be a slight hestitation as everything caught up. This slight hesitation was _very_ small and had no impact on the painting experience, but I could tell it was there. Under the RAM disk setup the hesitation was gone.

Filters, color adjustments and other misc PS takes ran about the same. Minor layer work seemed more snappy, but I had to be careful not to exceed my RAM disk size.

Results: Several benefits to scratching out to a RAM disk.

1) Slight increase in speed to fast strokes. No drive clicking. Less wear and tear on your HD.

2) I could increase my undo states with no speed penalty. On my system more than 6 states resulted in increased scratch times. Not much, but noticable. The need to have a dedicated HD partition was also gone. No worries about fragmented HD's. On the flip side, I have to worry about fragmented RAM now.

Issues:
1) Extensive layer work was out of the question. Not enough RAM.

2) I lost the ability to use the RAM allocated to the RAM disk for any other application. Not so hot in a general use environment where I want several memory-hungry apps open at once or the ability to throw my max RAM to one app like After Effects. I'd need to reboot.

Overall:
The speed increase was slight. My HD is a slow 5400rpm, running on an ATA33 controller. Even then it's fast enough to keep up w/ PS. On faster drives there might be no difference between RAM and HD speeds for scratch disking. My suggestion: don't bother unless you're paranoid about excessive drive activity or if you have a slow HD and an surplus of RAM. The setup was reliable and quick, but kind of a pain.

-Pat