Conundrum

Janice

Janice

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Janice
Edit My Images
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Can any of you computer bods help me please? :)

I am supposed to put my Photoshop scratch disc on another drive than where the operating system is (which is C), so I have it on my D drive which is big and fast with plenty of free space.

Now...the problem is when they say "put the scratch disc on another drive than the operating system, do they take into account that in Windows XP I have my pageing file, virtual ram, on the D drive.

So, to sum up.....is it the OPERATING SYSTEM that the scratch disc should be away from, or the virtual memory pageing files etc., as these are on different drives.
I dont know where to put the scratch disc.

Any help appreciated. Thank you.
 
I've always wondered the same thing, so rather than risk losing any more hair, I just leave scratchdisk on the C: drive. Never had any problems.
 
I think probably the latter, as when PS runs out of memory it will start to use the paging file to write to, and if it's writing to the scratch at the same time it will slow things down considerably. They automatically assume that the windows paging file is on the same volume as the Windows directory itself.

Doesn't affect me really, I only have the one drive at the moment, but when I get my upgrade later this month I'm gonna have 3 smaller Sata drives rather than one big one!

Sorry to Hijack your thread now but I also have a PS/hardware related question.......

I know CS2 is written to take advantage of multithreading, so will it make use of a dual-core amd chip if I get one? Or would i be better off with intel dual core (do these still support Ht?) so that i'd have effectively four processors
(2 cores hyperthreaded) also will 2gb of memory be enough ;) (it's dirt cheap at the mo)
 
So are you saying that you would put the scratch disc on c with windows but away from the pageing files on d?
 
It all depends on how much space is available on each drive, and how big the files are that your working on.
I wouldn't use the same drive the operating system is on.

Here's a few rules that should be observed when using scratch disks.

1. Scratch disks must be fixed physical hard drives or partitions - no network drives or removable drives - Jaz, Zips or CD-RW - can be used.

2. You should allocate your largest, emptiest, fastest hard drive as the "primary" scratch disk - the others won't get used until this one fills up.

3. Keep your primary scratch disk fairly empty if you can, and certainly keep it well defragmented and free from errors - use a disk checking program such as Windows' ScanDisk.

4. If the primary scratch disk fills up, you will have problems - hence the dreaded error message: "Could not complete your request because the primary scratch disk is full". This is often a Catch-22 - you will not be able to close the file because there is not enough temporary space, and unless you can delete something else from the drive you can't find enough space to save the file. You need to make sure that your primary scratch disk has free space equivalent to around five times your largest file and preferably equal to around twice the amount of RAM fitted in your computer.

5. Why twice the RAM? A little-known fact is that when Photoshop starts up it checks the available scratch disk space. If it can only find (say) 36Mb of scratch space, it will only use 36Mb of RAM, regardless of what you may have set in your preferences (see above). So if you are low on primary scratch disk space not only will you have trouble because of a lack of space for temporary files, but Photoshop will be using less real RAM to start with, making it more likely that it will need to use the scracth disk! So keep your scratch dirve empty and performance will be maintained.
 
The best configuration is to have three drives/partitions.

One for your operating system.
One empty one for your paging file.
One empty one for your scratch disk.

HTH
 
Gandhi said:
I know CS2 is written to take advantage of multithreading, so will it make use of a dual-core amd chip if I get one? Or would i be better off with intel dual core (do these still support Ht?) so that i'd have effectively four processors
(2 cores hyperthreaded) also will 2gb of memory be enough ;) (it's dirt cheap at the mo)
Click to expand...

Well I run with a 1Ghz CPU & only 512MB ram & have no real problems, so the 2GB should be fine (I have heard pro imagers have up to 4GB). It's all according to how many images you want open at once I suppose.
 
currently running athlon 1.8ghz (2500) and 512 here also. It's more that I have more than application open at the same time, but recently it's started grinding to a halt when I've been manipulating the 48mb tiffs I need for Alamy. I have to manipulate the full size version as doing it the other way, the image quality suffers too much!
 
Matt said:
The best configuration is to have three drives/partitions.

One for your operating system.
One empty one for your paging file.
One empty one for your scratch disk.

HTH
Click to expand...

You would only see a performance increase if they were seperated on 3 seperate physical disks.

You would see a performance decrease if you had one or two drives with multiple partitions and spread the pagefile and scratch disks across a single drive.

Basically what you are trying to achieve here is to increase the concurrent read/writes to your drives.

If you have one disk with 3 partitions and spread the OS, pagefile and scratch disk across each partition then you are forcing the heads of the disk to travel further to read/write data - hence causing a slowdown.

Hope this makes sense.
 
evilowl said:
You would only see a performance increase if they were seperated on 3 seperate physical disks.

You would see a performance decrease if you had one or two drives with multiple partitions and spread the pagefile and scratch disks across a single drive.

Basically what you are trying to achieve here is to increase the concurrent read/writes to your drives.

If you have one disk with 3 partitions and spread the OS, pagefile and scratch disk across each partition then you are forcing the heads of the disk to travel further to read/write data - hence causing a slowdown.

Hope this makes sense.
Click to expand...

He speaks the truth, it only works with physical drives, same with your paging file, if thats on a second partition you will gain no increase in performance. It and scratch disks must be on separate physical disks.

So ideally you might have
HDD0 Drive C: = O/S & Applications
HDD1 Drive D: = Paging File
HDD2 Drive E: = Scratch Disk

Add to this as much RAM as you can afford/fit as this is relative to the efficient size of the paging file (more RAM means a bigger paging file is practical, therefore overall increase in O/S performance).
Usually your paging file should be set at about 150% to 300% of your systems RAM, this is normally automatic and does not need to be altered.

Also try to ensure you have plenty of space free on your drives, and regular defraging (once a week, to once a month) should also give smoother performance.
 
Thanks very much for your replies everyone.

It seems I am doing it right, the best I can with only 2 physical drives.
I defragged yesterday, I have 1.5gb DDR RAM.
I do actuallly have an E partition but you say theres no point in putting anything on there as it wont increase performance?
 
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