Tips to Avoid Performance Issues (slowdowns, freezing, crashing)

While there are no minimum system requirements for Inkscape, a file size which challenges the system's resources is the primary culprit for performance issues in Inkscape.  Performance issues include work slowdowns, freezing and even crashing.  There may be other reasons for these issues, but the file size is the first thing to look at, for solving the problem.

Most importantly, starting with version 0.47, Inkscape has an AutoSave feature.  In version 1.0, it can be found in Preferences > Input/Output > AutoSave.

These things (not in any order) can increase the file size and potentially could be causing performance issues

• embedded raster images (in smaller systems, even just 1 large image could cause a problem)
• filters or combinations of filters (note that even a simple blur is a filter)
• certain extensions or number of uses of extensions
• large quantity of nodes (hundreds)
• a lot of gradients (tens)
• extreme zooming, or any zooming in a file that's already large
• a large number of unused defs (excess and unneeded data in the file)
• using the Objects dialog (Objects menu > Objects)
• various combinations of the above

And here are some ways to either avoid these issues, or to continue working in a file, when you already have these issues.

• The first thing you can do when you start to notice any of these issues, is to click File menu > Clean Up Document.  (Before version 0.91 it was File menu > Vacuum Defs.)  This will delete any data in the file that is not in use.  Especially if you're doing a lot of trial and error as part of your workflow, this data can accumulate, and slow down a file, even if there is very little content on the canvas.  If this doesn't help, or help enough, move on to the next things.
• Divide your file into layers, and maybe even sublayers.  Then you can hide all the layers that you don't need at the moment.  Since Inkscape doesn't display hidden layers, it frees up resources for whatever you're working on.
• If hiding layers won't work, because you still need to see them, as you continue to work, try this. 
  -- Temporarily hide the layers you're working on, and display all the others
  -- Select all
  -- Edit menu > Make a bitmap copy
  -- Move the new bitmap to a visible layer and hide the ones it's replacing
  -- Unhide the working layers
  -- When you're finished, don't forget to delete this bitmap copy
• Use View menu > Display Mode > Outline.  This prevents Inkscape from displaying gradients, filters, embedded raster images, etc.
• Use View menu > Display Mode > No Filters.  This prevents Inkscape from displaying filters only.
• If you can, link imported raster images rather than embedding.
• If you're using a computer with multiple cores/threads/processors (usually laptops) and have trouble with displaying filters, you can adjust some settings to better utilize the cores. 
  -- In version 1.0 this is in Preferences > Rendering > Number of Threads (has moved around in previous versions)
  -- On that same page, you can change "Gaussian blur quality for display" and "Filter effects quality for display"
• If you have a huge number of nodes, you might not need them, depending on the circumstances.  If not, you could try Path menu > Simplify, which potentially could drastically reduce the number of nodes. In certain situations though, it can distort the path, so just be ready to Undo, if the result is not acceptable.  Or it's possible to change the Simplification threshold, and have fewer nodes deleted at a time.  (Inkscape Preferences > Behavior > Simplification Threshold)  Note that selecting all the paths in the image, and applying Simplify will likely produce unacceptable results.  It's better to apply it to one or a few troublesome paths at a time.  Also, note that, starting with version 0.92, for the Pencil tool (which can create excessive number of nodes) there is a way to automatically simplify paths as you draw them, using the LPE Based Interactive Simplify option (look on the control bar).
• If you're using an embedded image as a reference, either delete it from the file as soon as you no longer need it, or move it to another layer where you can hide it.  Deleting would reduce the file's size much more.
• Avoid extreme zooming when possible, and zoom only as much as you need.
• Don't keep the Object dialog (Objects menu > Objects) open all the time.  Open it when you need it, and otherwise keep it closed.  (Developers are aware of this and planning a fix.)

If you have any questions, please feel free to post a message in our forum.