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The routing time might be longer than normal compared to the placement time. It is normal for routing time to be a third to half the placement time.
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Brad makes an excellent point. However, it is possible for the routing time to be equal to or, potentially, longer than placement. Typically, this occurs when one or more of the following conditions is true:
1) The design uses an excessive amount of wiring resources,
2) The design is using almost all of the logic resources (this causes very dense LABs to be created and the router needs to spend extra effort routing them),
3) Various "try harder" router optimizations are selected (e.g. set_global_assignment -name ROUTER_TIMING_OPTIMIZATION_LEVEL MAXIMUM), or
4) The design has a large number of very critical, balanced paths (e.g. a large crossbar)
It is possible that the different flows has caused one or more of the above conditions to change, which would ultimately explain the significant compile time difference between the two flows.
Honored Contributor
