Things that can slow performance in Civil 3D/AutoCAD

Last updated: 2020-10-26

There are many factors that contribute to overall system speed which can affect Civil 3D/AutoCAD performance.

  1. Hardware (CPU, hard drive, RAM, video card)
  2. Network (cable, switches, server)
  3. Operating system
  4. Software

  5. Files (number, size, objects within files, connections to other files)

The issues and solutions in this topic are not a complete list of every possible issue, but they give a good sampling of common issues and how to fix them.

Solution

Follow these guidelines to improve your AutoCAD performance. Determine which of them provides the best results for your environment. Not all guidelines have the same effect on all systems, so test and compare results.

Windows environment guidelines

Civil 3D/AutoCAD guidelines

  • Toggle hardware acceleration on and off to see which setting improves your performance. See How to enable or disable hardware acceleration in AutoCAD. 
  • Download and install the latest service pack and any hotfixes for your AutoCAD software. See Install Updates, Add-ons, and Enhancements.

  • Options dialog > Display tab > Turn off

    1. Show Tool Tips
    2. Show Rollover Tool Tips
  • Turn off Quick Properties QPMODE set to -1
  • Remove network paths from Options dialog > Files tab > Support File Search Path.
  • Remove any third-party plugins that are installed.
  • Clean up drawings with performance issues. See How to repair corrupt AutoCAD files. Examine highly nested blocks and consider exploding and purging them. 
  • Use the UCSICON command to activate the origin in the drawing. Determine whether any data or XREFs are located far from the origin. If so, use the MOVE command to relocate the data closer to the origin. Choose coordinates close to the origin when loading drawings via XREF.
  • Disable one or more system variables which may impact graphics performance: See Improving AutoCAD performance with older or low-end graphics cards

AutoCAD drawings which contain large amounts of text or hatches may degrade performance. In most cases this is due to older or low-end video cards, however, depending on the amount of data being displayed high-end graphic cards may be affected as well.

Causes

Several new system variables were introduced with AutoCAD 2015. These variables will display information about selection sets in the properties palette or high light objects when selected or hovered over. This may affect performance with some graphic cards.

Solution

  1. Close or Autohide the Properties palette until it's needed. 

  2. Change the following variables to off within AutoCAD (type them on the command line) until they are needed: 

Hides or displays annotative objects that do not support the current annotation scale.

The ANNOALLVISIBLE setting is saved individually for model space and each layout.

NOTE: When ANNOALLVISIBLE is set to 1, annotative objects that support more than one scale will only display one scale representation.

Value Description
0

Only annotative objects that support the current annotation scale are displayed
1

All annotative objects are displayed

Controls whether a preview of the possible outcome of the command is displayed.

NOTE: The SELECTIONPREVIEW system variable value is ignored when COMMANDPREVIEW is on.

Value Description
0

Off
1

On

Controls the default display behavior of overlapping objects when they are created or edited.

Info: Full draw order display may slow some editing operations.

Value Description
0

Turns off the default draw order of overlapping objects: after objects are edited, regardless of their draw order, the objects are displayed on top until a drawing is regenerated (REGEN) or reopened. This setting also turns off draw order inheritance: new objects that are created from another object using the commands listed below are not assigned the draw order of the original object. Use this setting to improve the speed of editing operations in large drawings. The commands that are affected by inheritance are BREAK, FILLET, HATCH, HATCHEDIT, EXPLODE, TRIM, JOIN, PEDIT, and OFFSET.
1

Turns on the default draw order of objects: after objects are edited, they are automatically displayed according to the correct draw order.
2 Turns on draw order inheritance: new objects created from another object using the commands listed above are assigned the draw order of the original object.
3 Provides full draw order display. Turns on the correct draw order of objects, and turns on draw order inheritance.

Turns Dynamic Input features on and off.

When all features are on, the context governs what is displayed.

If dynamic prompts are on ( DYNPROMPT is set to 1), they are displayed when DYNMODE is set to 1, 2, or 3.

When DYNMODE is set to 1, 2, or 3, you can turn off all features temporarily by holding down the temporary override key F12

Value Description
0

All Dynamic Input features, including dynamic prompts, off
1

Pointer input on
2 Dimensional input on
3 Both pointer input and dimensional input on

Controls the amount of space allocated in DWG files for incremental saves, which affects the number of quick save operations that can be performed before a full save is required.

When the file save estimate exceeds the specified percentage, the next save will be a full save. Valid values can range from 0 to 100 percent.

  • A value of 0 means that all save operations are full saves. A full save optimizes the size of a DWG file, but is noticeably slower on large drawings.

  • A value of 100 increases the space available to append changes to the maximum possible. This value results in the greatest number of incremental quick save operations between full saves at the expense of larger file sizes.

Info: Saving to a different format always results in a full save.

Specifies how the display list is updated in the Model tab and layout tabs.

For each tab, the display list is updated either by regenerating the drawing when you switch to that tab or by saving the display list to memory and regenerating only the modified objects when you switch to that tab.

The performance gain achieved by changing the LAYOUTREGENCTL setting is dependent on several factors, including the drawing size and type, the objects contained in the drawing, the amount of available memory, and the effect of other open drawings or applications. When LAYOUTREGENCTL is set to 1 or 2, the amount of additional memory used is the size of the Model tab's display list multiplied by the number of viewports in each layout for which the display list is saved.

If LAYOUTREGENCTL is set to 1 or 2 and performance seems slow in general or when you switch between tabs for which the display list is saved, consider changing to a setting of 0 or 1 to find the optimal balance for your work environment.

Regardless of the LAYOUTREGENCTL setting, if you redefine a block or undo a tab switch, the drawing is regenerated the first time you switch to any tab that contains saved viewports.

Value Description
0 The drawing is regenerated each time you switch tabs.
1

For the Model tab and the last layout made current, the display list is saved to memory and regenerations are suppressed when you switch between the two tabs. For all other layouts, regenerations still occur when you switch to those tabs.
2 The drawing is regenerated the first time you switch to each tab. For the remainder of the drawing session, the display list is saved to memory and regenerations are suppressed when you switch to those tabs.

Constrains cursor movement to the perpendicular.

When ORTHOMODE is turned on, the cursor can move only horizontally or vertically relative to the UCS and the current grid rotation angle

Value Description
0 Turns off Ortho mode
1

Turns on Ortho mode

Controls whether palettes can be made transparent.

When transparency is available and turned on, use the Transparency option on the shortcut menu to set a different degree of transparency for the current palette or for all palettes.

When hardware acceleration is enabled, the settings 2 and 3 are available; when disabled, only the settings 0 and 1 are available.

Value Description
0

Palette transparency is turned on
1

Palette transparency is turned off
2 Transparency is turned on and is not supported by the hardware or operating system
3 Transparency is turned off, but is not supported by the hardware or operating system

Controls whether you can preview the changes to currently selected objects when you roll over drop-down lists and galleries that control properties.

Info: Property previews are displayed only from the ribbon and the Properties palette. They are not available from other palettes.

Value Description
0 Turns off rollover property previews
1

Displays rollover property previews

Controls whether the Quick Properties palette is displayed when objects are selected.

Value Description
0 Turns off the display of the Quick Properties palette for all objects when they are selected in the drawing area
1

Turns on the display of the Quick Properties palette for all objects when they are selected in the drawing area
2 Turns on the display of Quick Properties palette, but only for objects that are supported in the Customize User Interface (CUI) editor for displaying quick properties when they are selected in the drawing area

Controls the display of rollover tooltips when the cursor hovers over an object.

The content in tooltips can be customized in the Customize User Interface (CUI) Editor.

Value Description
0 Object rollover tooltips are not displayed
1

Object rollover tooltips are displayed

Controls the visual fidelity for annotative objects in AutoCAD 2007 and earlier.

This setting affects drawings only when saving to AutoCAD 2007 or earlier file formats.

Controls the display options associated with overlapping objects and selection cycling.

Ctrl+W to toggle the current setting on and off.

When you roll over overlapping 2D objects, options are available to alert you and let you select between the objects.

Value Description
0 The display options are turned off
1

A badge displays when you hover over objects that overlap
2 Both a badge and the Selection dialog box displays

Controls the display of selection previewing.

Objects are highlighted when the pickbox cursor rolls over them. The highlighting indicates that the object would be selected if you clicked it. The setting is stored as a bitcode using the sum of the following values:

Info: The SELECTIONPREVIEW system variable value is ignored when COMMANDPREVIEW is on.

Value Description
0 Off
1

On when no commands are active
2 On when a command prompts for object selection

Turns the Snap mode on and off in the current viewport. (grid snap)

Value Description
0

Off
1

On

Controls whether dynamic UCS acquisition is active when creating objects involving 3D planar surfaces.

You can align the UCS dynamically when your cursor hovers over a planar face on a 3D solid, a planar mesh element, or a planar point cloud segment while as you create an object.

Info: Dynamic UCS alignment does not detect planar surface objects or 2D geometry.

Value Description
0

Not active
1

Active

Controls whether to use an additional processor to improve the speed of operations such as ZOOM that redraw or regenerate the drawing.

WHIPTHREAD has no effect on single processor machines.

When multithreaded processing is used for redraw operations (value 2 or 3), the order of objects specified with the DRAWORDER command is not guaranteed to be preserved for display, but is preserved for plotting.

Value Description
0 No multithreaded processing; restricts regeneration and redraw processing to a single processor. This setting restores the behavior of AutoCAD 2000 and previous releases.
1 Regeneration multithreaded processing only; regeneration processing is distributed across two processors on a multiprocessor machine.
2 Redraw multithreaded processing only; redraw processing is distributed across two processors on a multiprocessor machine.
3 Regeneration and redraw multithreaded processing; regeneration and redraw processing is distributed across two processors on a multiprocessor machine.

If you are running Windows Vista or Windows 7, try turning off Aero by setting your desktop theme to Windows Basic.

How to repair a damaged or corrupted AutoCAD drawing (.dwg) file. A drawing may have one or more of the following symptoms: 

  • Drawing file does not open. 
  • Drawing file opens with errors. 
  • File hangs or crashes AutoCAD. 
  • Slow performance when editing a file. 
  • Error messages appear when working in a file. 
  • Commands do not work or are delayed. 
  • Unexplained increase in file size.  
  • Display or regen problems. 
  • Drawing elements missing or shown incorrectly. 

Causes

  • Third-party software is running within AutoCAD. 
  • Non-Autodesk or non-RealDWG product created or saved the file.
  • AutoCAD terminated while saving a drawing file, such as during a power surge or outage. 
  • Old drawings have been used repeatedly over a long time period. 
  • Network anomalies have occurred (such as transmission errors, file locking, and latent writing of data). 
  • Storage media has degraded (such as bad sectors on a hard drive).
  • System RAM is failing or defective.
  • Operating system issues exist.

Solutions

Work through the following solutions as listed: