Fitter Preservation Level

Allows you to specify the amount of information that you want the Fitter to preserve from the specified netlist file. The default value is the highest degree of placement supported by the device family. The following table describes the Fitter Preservation Level settings.

Note: The Fitter Preservation Level is an advanced setting. The default Fitter Preservation Level for partitions with a Post-Fit netlist type is the highest level of preservation available for the target device family and provides the greatest reduction in compilation time.
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Fitter Preservation Level

Quartus® Prime Software Behavior for Partition During Compilation

Placement and Routing

Preserves the design partition"™s netlist atoms and their placement and routing in the design

partition. This setting maximizes performance preservation for timing-critical paths.

To preserve high-speed optimization for programmable power tiles in devices with programmable power tiles, refer to the Advanced tab in the Design Partitions Properties dialog box.

Placement

Preserves the netlist atoms and their placement in the design partition. Re-routes the design

partition.

Netlist Only

Preserves the netlist atoms of the design partition, but replaces and reroutes the design partition.

A post-fit netlist with the atoms preserved can be different from the Post-Synthesis netlist because it contains Fitter optimizations; for example, Physical Synthesis changes made during a previous

Fitting. You can use this setting to complete the following tasks:

  • Preserve Fitter optimizations, but allow the software to perform placement and routing again.
  • Reapply certain Fitter optimizations (such as Fitter, physical synthesis) that would otherwise be impossible when the placement is locked down.
  • Resolve resource conflicts between two imported partitions.