Note: This is a repeat of a previous post. Why? Because I’m on a sub-tropical island and may not have the time to make any posts. With any luck, I’ll bring back some stories and pictures for the future.
Have you ever been plodding along in Photoshop, only to find yourself waiting for it to process a command or redraw your image? Of course you have, if you’re doing anything beyond entry-level editing. Now let me ask you this question – have you ever done anything about it?
What Can I Do to Improve Photoshop Performance?
As it happens, there are some very simple things you can do to make Photoshop run more smoothly. Some cost money, but many options are within your grasp without any expense at all. The first thing you need to do is visit your Performance Preferences.
A few simple changes here can improve your performance. Let’s start with your Memory Usage. By default, it’s set to use up to 70% of your RAM. Adobe claims that you can use up to 100% with no performance degradation if you’re running Photoshop in 64-bit mode and not running any other applications. Personally, I keep mine at 70% even though I have it running in 64-bit mode. There’s never a time when I’m not running another application. I generally quit other major applications, but I need my iTunes music playing while I process.
The Photoshop Optimization section on MacPerformanceGuide.com suggests you would do well to keep your default settings, though, due to a bug on Mac OS X. Using a larger percentage of RAM could seriously degrade your performance. However, the site notes that adding more RAM is perhaps one of the best performance improvements you can make. That makes sense, since you want to eliminate reasons for the application to touch the disk. Surprisingly, too much RAM yields worse results. 24 BG seems to be the sweet spot, but 16 will do nicely. Even if you have a laptop or older system that won’t accept that much RAM, add what you can.
If you can’t add enough RAM to prevent Photoshop from needing to use a Scratch Disk, then make sure it’s using the fastest scratch disk you have. In my screen shot above, I have three disks available. The first one (checked) is my internal hard drive – a 7200RPM 1GB drive. The next is my RAID array, connected by FireWire 800, and the last one is a USB drive. While the multiple disks working on the RAID array may be faster than a single drive, the slow connection of FireWire or USB rules out those other drives. Ideally, using a Solid State Drive to boot and use for a Scratch Disk would yield the best performance. Check your settings to ensure you’re using your fastest disk.
While you’re doing that, check how much usage is on that disk. Hard drives give their best performance when they are less than 50% full. If your fastest drive is 80% full, it may not yield your fastest results. Better to move some of those files elsewhere to get your best performance.
The History & Cache section has three buttons with presets to change the fields below them. Ignore them. You can figure out the best settings by yourself.
History States are basically the number of times you can Undo changes while editing in Photoshop. 20 is the default, but it can go up to 1,000. Keep in mind that every one of those states takes up resources – reducing the amount of RAM you have available for other actions. Use that RAM for 1,000 history states and you increase the likelihood that Photoshop will use your scratch disk – which is much slower than RAM.
Cache Levels also use resources, but it can help speed up redraw times. Think of it as an investment. If your resource is holding something that you’re working on at the moment, Photoshop doesn’t have to go back to load something from disk to redraw it. According to Adobe’s Tech Note to Optimize Performance, this setting should be greater than the default value (4) for images over 10 Megapixels. If you’re editing images from a modern DSLR, that’s almost certainly the case if you load the full size image for editing.
Cache Tile Size comes with the lowest default setting (128K), which is almost certainly the worst choice for Photoshop. Mac Performance Guide notes that this setting is critical to performance. Think of your Cache Tile Size as a bucket that fetches bits from your Cache Levels. A smaller bucket means the system has to make more trips to get everything it needs. Help it out. Give it a bigger bucket and select 1028K.
These are just a few tips, but they can give you some interesting improvements. You should check out the Adobe Optimize Performance note and the other recommendations from Mac Performance Guide for more ideas, even if you run on a Windows machine.