PS slow downs with external hard drive attached.

[mbalensiefer]

Any external hard drive that I attach to my computer simply seems to lock up PS for some time...especially during Liquify actions. When this occurs, I even have a hard time getting Explorer to move. I do not have any swap file actions going on in my external hard drive, and my photos/work lay on my "C" drive. Sometimes during the lockup, I pull the plug (USB port) on my hard rive, and all snaps back to life instantly. PS is not set to use any other drives.

It has been this way for me on all my computers, and with CS versions 4 and 5. I really need to solve this problem, as it's a production killer.

Michael

[stamper]

Why do you need it active? Are you working on an image stored there? Could you not move the image from the external drive first. Again you don't provide information why you have it active.

[mbalensiefer]

It is just attached, as it always is. My images are on my C drive.

[Mark D Segal]

You shouldn't work on images between an external drive and the operating system altogether. It's a total productivity killer. Import the image to your local drive, work it, save it, then re-export it to the external.

[mbalensiefer]

Yes. my images are on my C drive.

[Mark D Segal]

OK. Then this suggests the problem has little to do with Photoshop and more to do with the performance of your USB connections. They can cause problems. Is your HD plugged directly into one of the computer's native USB port, or to a derivative port? Have you tried switching USB connection between back and front ports to see whether that makes a difference? I suggest this, because I recently had intermittent performance issues with a scanner connected to a USB card plugged straight into my Mac, but it caused hangs, which seem to have disappeared once I connected the scanner to one of the computer's native USB ports, as recommended by the tech support I contacted. They advised that non-native USB ports can be temperamental in any computer.

[Steve Weldon]

Any chance PS is set up to use the external as a scratch disk?  See what boxes are checked in the preferences and uncheck the USB drive if checked.

[Mark D Segal]

That's an excellent point. Could be the problem. Ideally, the scratch disk should be on an internal HD separate from the HD on which the application itself is running.

[mbalensiefer]

So far after having swapping USB ports I am having better luck.

[Mark D Segal]

Good.

[louoates]

The other time hog has nothing to do with the external HD. It is the history state setting. Try clearing the history states if you don't need to jump backwards for that image. That will reset the performance setting on your Photoshop Info palate to 100%, meaning that you are again using 100% of ram memory and not accessing-- and waiting-- for scratch memory. If you don't need many history states you can reset it in the preferences>performance section. I have mine set to 60 history states but many times I need to clear history to get back to 100% performance. But many of my files are 2+ gigs.

[mbalensiefer]

By clearing History States do you mean for the one file that you are working on?

[louoates]

Yes, it's the only file affected. And you can clear the history as many times as you need to. Every time you open that file again...and any new file you open will revert to the number of history states in your preferences.

[schrodingerscat]

I've found that USB is not the best for intensive PS work. Firewire works much better, and would expect the same for ESATA. Have also found it makes a big difference when transferring large collections of files or backing up/archiving. Especially if backing up a bootable drive.

Internally or externally, for best results scratch disks should be a separate dedicated fast(at least 7200 RPM) drive with no OS installed. When I was using a laptop as my primary box, I had a small fast firewire drive as a scratch. Internal is always better if you have the room.

[Justan]

Every time a (Windows) computer does a file I/O it will wait a specified amount of time for anything that is a drive to respond. This is done to accommodate slow connections, such as happens with dial up, or some VPN/WAN connections, some SAN and NAS drives, CD/DVD drives, some USB drives.

Another part of this issue is that many vendors configure USB drives to spin down after an amount of time, when the drive is unused. This is done to save energy and/or extend the life of the drive. And, of course, being a USB drive there is an added chance of issues related to the cable or USB interface.

There are a variety of fixes for this kind of thing. Some are registry fixes to change the amount of time Windows will wait before giving up on a drive or LAN/WAN connection. Some are tweaks that can be done to some drives to stop them from spinning down, some are replacing faulty USB or drive interfaces.

The worst scenarios I've seen are when someone has a USB drive connected to a server or a CD/DVD disk in the drive tray. Every time the server has to do file i/o it has to wait for the USB or CD drive. When the drive spins down, the server performance degrades.

I can’t tell you how many times I've been asked to look at “serious server performance issues,” only to find that there is a dead network connection to another server, a faulty USB drive, or a DVD left in the server’s DVD drive bay as the root causes.

BTW, the best scratch and/or paging drives are the latest generation of SSD drives. You can buy them for about $80 and upward. These are *way* faster than using any other kind of media other than perhaps a RAM drive.

[mbalensiefer]

Great--thanks all for the replies!

 I have upgraded my external hard drive to eSata--and the speed seems about 6 times as fast as over USB.
 Now, does anyone have this issue: my external drive is two 1TB drives set in JBOD. Both drives worked fine over USB, but now over eSata I am only getting one drive to show. Swapping the drives in their respective slots results in the other drive being recognized.

Michael

[Justan]

I haven’t used them personally but an article I read stated the JBOD drives uses 1 or more physical drives and presents them to the OS as 1 logical drive.

So the question is: does the drive capacity change when you have more than one drive connected?

[Eric Myrvaagnes]

I haven’t used them personally but an article I read stated the JBOD drives uses 1 or more physical drives and presents them to the OS as 1 logical drive.

So the question is: does the drive capacity change when you have more than one drive connected?

That's my understanding as well. With both drives connected the "single drive" capacity should be about equal to the sum of the capacities of the two separate drives.

Eric

[mbalensiefer]

Hi,
 Over USB both drives show as two separate (1TB) drives (mapped as O and S drives) for 2TB of space total.
 Over the eSATA connection, my external enclosure shows only one of the drives (whichever drive I've placed in the "O" bay).

[Pete_G]

A JBOD is "just a bunch of drives", that is to say that a 5 drive JBOD array will present itself to the OS as 5 distinct and separate drives. To "stripe" them together would involve using RAID, preferably hardware RAID as opposed to software RAID.