How to config photoshop CS3 memory usage

[soboyle]

I have a new PC running Vista 64 bit with 8 gigs of ram. Any suggestions on how to best use this amount of ram for photoshop?
Photoshop only shows 3.25 gigs available, any tricks to allow use of more ram?
John Choy suggested using a 4 gig ram disk as a photoshop scratch disk. Is there any more direct way of utilizing the ram, a photoshop plug in that will give access to more memory?

[Paul2660]

Currently I don't think there is a way to assign CS3 to use more than the amount you have seen.  However CS3, I believe on a 64 bit machine will use some of the 8GB for scratch.  It will write to the RAM before it writes to your assigned scratch disks. I don't know how to control that however.  


Paul C

[tagor]

CS3 is a 32 bit app, so it can only use 4GB address space. It doesn't show you the full 4GB, since it leaves some space for things like plugins.

Photoshop doesn't use the rest of the memory, it will be used by Vista as disk cache, so you get some benefit. Using the Ram disk will be faster.

-- Tilo

[Ken Rahaim]

Using the Ram disk will be faster.

Is there a way to set up a RAM disk on a Mac running OS X 10.5? I've got 10GB of RAM and could spare a bit of it for a RAM disk since pshop is all my workstation does..

[Schewe]

Is there a way to set up a RAM disk on a Mac running OS X 10.5? I've got 10GB of RAM and could spare a bit of it for a RAM disk since pshop is all my workstation does..
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On Mac, you REALLY don't want to waste the ram on a Ram Disk...seriously. If you have more ram than say 6-8 gigs, then you'll want to download the VM Buffering plug-in. See: [a href=\"http://photoshopnews.com/2007/05/29/photoshop-cs3-vm-buffering-optional-extensions-mac-only/]Photoshop CS3 VM Buffering Optional Extention[/url]

[Paul2660]

The way it's been explained to me:

On my 64 bit XP machine I have 8GB of ram installed.  
Even though CS3 is a 32 bit applicaiton, you still are stopped at 3.25GB  At least this is the max you can tell it to work with.  CS3 is still a 32 bit app, loaded in the x386 folder.  

From talking to other 64 bit users, I have been told  that CS3/XP OS  can use some of the rest of the 8GB (not the 3.25GB you have assigned it) to create a virtual scratch disk.  It will write to this disk in ram first, then to your assigned scratch disks.  I have tried to find more in print to explain this process, but haven't found anything.  

Paul C

[jerryrock]

From Adobe Tech note regarding 64bit processor and Vista64 bit with over 4 gigs of ram:

"If you have more than 4 GB (to 6 GB), then the RAM above 4 GB is used by the operating system as a cache for the Photoshop scratch disk data. Data that previously was written directly to the hard disk by Photoshop is now cached in this high RAM before being written to the hard disk by the operating system."

The complete Tech note on Photoshop CS3 Optimization for XP and Vista:

http://www.adobe.com/go/kb401088

Jerry

[johnchoy]

My memory usage setting in PS is around 50%. Some even mention 30% will be enough. My habit of PS together w/ other windows application is best to be around 50%. I found it's only the faster the disk scratch, the higher the performance will be.

Don't know much about vista, but on my x64 computer w/ 8 gig ram, a ramdisk as the first scratch disk ( a 2nd scratch disk by a raid 0 of a pair of WD raptor) is faster and more efficient than w/o a ramdisk.

Some function of PS utilise windows swapfile and temp too ( I observe especially in the case of merge to HDR is ), so " RAM above 4 GB is used by the operating system as cache " may not be beneficial all the time. A mandatory extra ram addressing such as the use of ramdisk as scratch disk will surely help.

[Paul2660]

thanks Jerry for the link, I have been looking for that.

Paul C

[8x10nut]

For a change, it is actually not an OS issue. You probably have to enable the motherboard's memory remapping feature, if available.
http://support.microsoft.com/?scid=kb%3Ben...29605&x=13&y=19

MS probably had enough of calls related to this, and decided to play dirty:

http://support.microsoft.com/kb/946003/

With SP1 (unless you dig deeper) Vista will show you how much physical memory the computer has installed, not how much it can use. Nice one, Microsoft.

As far as ramdisk, you can pay http://www.superspeed.com/desktop/ramdisk.php and http://www.cenatek.com/product_page_ramdisk.php or you can play for free http://www.ltr-data.se/opencode.html#ImDisk (ideas for Unsigned drivers workarounds here: http://www.boot-land.net/forums/?showtopic=3498) or you can go in-between: http://www.ramdisk.tk/.

As far as the Adobe note Jerry provided, I have the feeling that what Adobe meant to say was:
"If your OS can see more then 4 GB (to 6 GB)  ..."
What the OS can not see, Adobe can't see either. That is probably also the case for all the ramdrive solutions.

BTW, what's with the "to 6 GB" (other than the 'Additionally, in Windows Vista 64-bit, processing very large images is much faster if your computer has large amounts of RAM (6-8 GB).' note )  limit in that article ? If you have more - say 8 GB - what will happen ? The RAM above 4 GB is will not be used a cache for the Photoshop by the OS at all, or only 2 GB will be used regardless of how much of RAM you have > 6 GB ?

Looks like memory remapping is your best friend.

[Ken Rahaim]

MS probably had enough of calls related to this, and decided to play dirty:

http://support.microsoft.com/kb/946003/

With SP1 (unless you dig deeper) Vista will show you how much physical memory the computer has installed, not how much it can use. Nice one, Microsoft.

As far as ramdisk, you can pay http://www.superspeed.com/desktop/ramdisk.php and http://www.cenatek.com/product_page_ramdisk.php or you can play for free http://www.ltr-data.se/opencode.html#ImDisk (ideas for Unsigned drivers workarounds here: http://www.boot-land.net/forums/?showtopic=3498) or you can go in-between: http://www.ramdisk.tk/.

I couldn't help but chuckle when I read this. It reminded me of all the workarounds we used to jump through hoops for to get around MS-DOS 640 kilobyte limitation      !

We've come so far yet we still have so far to go .

[jecxz]

I couldn't help but chuckle when I read this. It reminded me of all the workarounds we just to jump through hoops for to get around MS-DOS 640 kilobyte limitation      !

We've come so far yet we still have so far to go .
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Edit the config.sys to read:

device=himem.sys
dos=high,umb
device=emm386.exe noems

That's all there was to it! What are you complaining about?

[Ken Rahaim]

Edit the config.sys to read:

device=himem.sys
dos=high,umb
device=emm386.exe noems

That's all there was to it! What are you complaining about?

Ha ! Yeah, I recall that. It was such a breakthrough when we could finally address more than 1 megabyte of main memory (geez, just one of my Apple's CPUs has 12 times that amount of memory just for level 2 cache ).

But before that, you probably recall there were all kinds of TSR's we juggled to stay under 640KBs  .

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[jecxz]

Ha ! Yeah, I recall that. It was such a breakthrough when we could finally address more than 1 megabyte of main memory (geez, just one of my Apple's CPUs has 12 times that amount of memory just for level 2 cache ).

But before that, you probably recall there were all kinds of TSR's we juggled to stay under 640KBs  .

</end hijack>
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I remember, I used to write TSRs (Terminate and Stay Resident programs (for those who don't know)) in assembly language. Good to ride down memory lane, pun intended.