Performance preferences

Photoshop provides a set of preferences (Preferences > Performance) to help you make optimum use of your computer's resources, such as memory, cache, graphics processor, displays, etc. Depending on your primary use case for using Photoshop and the types of documents you generally work with, different combinations of these settings may suit you. Additional settings such as Scratch Disks, available on other tabs of the Preferences dialog, may also directly impact your computer's running speed and stability.

You can improve performance by increasing the amount of memory/RAM allocated to Photoshop. The Memory Usage area of the Performance preferences screen (Preferences > Performance) tells you how much RAM is available to Photoshop. It also shows the ideal Photoshop memory allocation range for your system. By default, Photoshop uses 70% of available RAM.

1. Increate the RAM allocated to Photoshop by changing the value in the Let Photoshop Use box. Alternatively, adjust the Memory Usage slider.
2. Restart Photoshop to enable your changes.

To find the ideal RAM allocation for your system, change it in 5% increments and monitor performance in the Efficiency indicator. See Keep an eye on the Efficiency indicator.

We don't recommend allocating more than 85% of your computer's memory to Photoshop. Doing so may affect performance by leaving no memory for other essential system applications.

Photoshop uses image caching to speed up the redrawing of high-resolution documents while you're working on them. You can specify up to eight levels of cached image data and choose one of the four available cache tile sizes.

Increasing cache levels improves Photoshop’s responsiveness while you work, although images may take longer to load. The cache tile size determines the amount of data on which Photoshop operates at a time. Bigger tile sizes speed up complex operations, such as sharpening filters. Smaller changes, such as brush strokes, are more responsive with smaller tile sizes.

Three cache presets are available in the Performance preferences. Choose the one that matches your primary use case/purpose of using Photoshop:

• Web/UI Design: Choose this option if you use Photoshop primarily for web, app, or screen design. This option is appropriate for documents having numerous layers of low-to-medium pixel dimension assets.
• Default/Photos: Choose this option if you use Photoshop primarily to retouch or edit moderate-sized images. For example, use this option if you normally edit photos originating from your mobile or digital camera in Photoshop.
• Huge Pixel Dimensions: Choose this option if you work extensively with heavy documents in Photoshop; for example, panoramas, matte paintings, etc.

For finer control, specify cache levels manually; the default value is 4.

• If you use relatively small files—roughly 1 megapixel or 1280 by 1024 pixels—and many layers (50 or more), set Cache Levels to 1 or 2. Setting Cache Levels to 1 disables image caching; only the current screen image is cached.
• If you use files with larger pixel dimensions—say, 50 megapixels or larger—set Cache Levels higher than 4. Higher cache levels speed up redrawing.

You can save scratch disk space and improve performance by limiting or reducing the number of history states Photoshop saves in the History panel. The amount of space you save varies depending on how many pixels an operation changes. For example, a history state based on a small paint stroke or a non-destructive operation, such as creating or modifying an adjustment layer, consumes little space. Applying a filter to an entire image, on the other hand, consumes much more space.

Photoshop can save up to 1,000 history states; the default number is 20. To reduce that number, go to the Performance preference dialog box, choose History & Cache > History States. In the History States pop-up menu, if necessary, drag the setting to a lower value.

The best way to optimize GPU acceleration, which speeds up screen redraws, is to keep your video adapter driver up to date. For more information about GPU acceleration and instructions on updating video adapter drivers, see Photoshop GPU and video card FAQ.

Turning on OpenCL, a technology that lets applications use the GPU, is likely to improve performance if you use these Photoshop features:

• Video Panorama
• Blur Gallery (Iris, Field, and Tilt-shift Blur)

To turn on OpenCL, in the Performance Preferences panel, click Advanced Settings and select Use OpenCL.

Photoshop provides you with dedicated GPU settings in both the Performance and 3D sections in the Preferences dialog.

Settings in the Preferences > Performance section

If a suitable video card is installed on your system, it will appear in the GPU Settings area of the Performance section.

• To enable GPU acceleration, make sure that the Enable OpenGL Drawing option is selected.
• To fine-tune the card’s performance, click the Advanced Settings button and select Basic, Normal, or Advanced, matching the option with your requirements.
  • Basic—Uses the least amount of GPU memory to run the most basic OpenGL features when sharing the GPU with other applications or when experiencing slow responsiveness. Select this option if you have other programs running that also use the GPU or if you notice bad screen redraws or slower performance when using GPU-accelerated features.
  • Normal—Is the default setting. It uses a large amount of GPU memory to support advanced OpenGL features and should be selected if you regularly use the GPU-accelerated features in Photoshop.
  • Advanced—Uses the same amount of memory as the Normal mode, but enables more advanced features to improve drawing performance. This setting is best when working in 3D or when working extensively with the GPU-accelerated features.

Note: Mode changes take effect only after Photoshop is restarted.

Settings in the Preferences > 3D section

The 3D section of the Performances dialog box contains a VRAM slider similar to the memory control located in the Performance section. Use the slider to determine the upper limit of the video RAM (VRAM) available to the Photoshop 3D engine. The total value is a percentage of the overall VRAM available. A setting of 100% will still reserve a portion of the overall VRAM for use with the operating system. Higher values will help with overall 3D performance but may compete with other GPU-enabled applications.

A scratch disk is any external or internal drive or drive partition with free memory. By default, Photoshop uses the hard drive on which the operating system is installed as the primary scratch disk. You can tweak scratch disk settings in the Preferences > Scratch Disks section.

1. Choose Edit > Preferences > Scratch Disks (Windows) or Photoshop > Preferences > Scratch Disks (Mac).
2. To enable or disable a scratch disk, select or deselect the Active check box. To change the scratch disk order, click the arrow buttons.
3. Click OK.
4. To apply the changes, restart Photoshop.

• For best performance, connect the scratch disks to a compatible port that has the highest bandwidth limit of all the available ports. The bandwidth limits for various ports are as follows:
  Thunderbolt = 10GB/sec
  eSATA = 600MB/sec
  PCIe = 500MB/sec
  USB3 = 400MB/sec
  USB2 = 35MB/sec
• To improve performance, set the scratch disk to a defragmented hard disk that has plenty of unused space and fast read/write speeds. If you have more than one hard drive, you can specify additional scratch disks. Photoshop supports up to 64 exabytes of scratch disk space on up to four volumes. (An exabyte equals 1 billion GB.)
• If your startup disk is a hard disk, as opposed to a solid-state disk (SSD), try using a different hard disk for your primary scratch disk. An SSD, on the other hand, performs well as both the primary startup and scratch disk. In fact, using an SSD is probably better than using a separate hard disk as your primary scratch disk.
• Scratch disks should be on a different drive than any large files you are editing.
• Scratch disks should be on a different drive than the one your operating system uses for virtual memory.
• RAID disks/disk arrays are good choices for dedicated scratch disk volumes.
• Defragment drives with scratch disks regularly.

Watch the Efficiency indicator to monitor performance while you work in Photoshop. Click the pop-up menu at the bottom of the image window and choose Efficiency from the pop-up menu.

If the value in the indicator is below 100%, Photoshop has used all available RAM and is using the scratch disk, which slows performance. If the efficiency is less than 90%, allocate more RAM to Photoshop in Performance preferences. Or, add more RAM to your system.

The Performance > File Handling > Automatically Save Recovery Information Every n Minutes option may have a bearing on performance as well. The Save In Background preference is enabled by default. When it is on, Photoshop lets you continue working while Save and Save As commands are performed, instead of requiring you to wait until they complete. The Automatically Save Recovery Information preference is enabled only if Save in Background is on. When enabled, recovery information is saved for each open file at the specified interval. (Recovery information is saved as a redundant backup; your original file is not modified.)

Usually, background save operations do not significantly affect the performance or responsiveness of normal Photoshop operations. However, if you are editing a file that is much larger than available RAM, the save operation can affect responsiveness or performance until the save is complete.

If Photoshop seems to intermittently slow down, you can check whether background save is affecting performance. Choose Save Progress in the status pop-up menu on the lower left of your image window.

If you notice performance issues while the Save Progress bar is moving, go to Preferences > File Handling, and decrease the frequency of the Automatically Save Recovery Information preference. Or, turn off the preference.

Setting a lower value for the recovery interval gives you more protection against crashes. In most cases, saving the recovery information does not affect the performance or responsiveness of Photoshop. However, a slowdown in performance is most likely if the files you’re modifying are larger than the available RAM.

Recovery information is saved in the same locations as the Photoshop scratch files. If you regularly keep many large files open while working, the amount of space can be significant. If you get out-of-disk-space errors while performing commands other than Save commands, add scratch disk space. Or, disable the Automatically Save Recovery Information preference.

Watch the Efficiency indicator to monitor performance while you work in Photoshop. Click the pop-up menu at the bottom of the image window and choose Efficiency from the pop-up menu.

If the value in the indicator is below 100%, Photoshop has used all available RAM and is using the scratch disk, which slows performance. If the efficiency is less than 90%, allocate more RAM to Photoshop in Performance preferences. Or, add more RAM to your system.