Abaqus/CAE records your changes to the current sketch in a cache that enables you to undo and redo several consecutive sketching changes. By default, the undo cache supports up to 10 levels of undo, but you can increase or decrease this number. You might want to increase the number of levels if your sketching operations require large-scale changes, and you might want to decrease this number to improve system performance for large, complex sketches.
The maximum number of undo levels applies to all sketches in the Abaqus/CAE session. Abaqus/CAE clears the undo cache each time you change the current sketch or switch to a different module.
To set the maximum number of recorded sketching operations:
From the bottom of the Sketcher toolbox, select the customization tool 
.
The Sketcher Options dialog box appears.
From the General tabbed page, enter a value from 0 to 100 in the Max level for sketch undo text field.
After you have chosen the desired customization options, click OK to apply your changes and to close the Sketcher Options dialog box.
