When analyzing congestion, the level reported by the tools can be categorized as shown in the following table.
Note: Congestion levels of 5 or higher often impact QoR and always lead to longer router runtime.
| Level | Area | Congestion | QoR Impact |
|---|---|---|---|
| 1, 2 | 2x2, 4x4 | None | None |
| 3, 4 | 8x8, 16x16 | Mild | Possible QoR degradation |
| 5 | 32x32 | Moderate | Likely QoR degradation |
| 6 | 64x64 | High | Difficulty routing |
| 7, 8 | 128x128, 256x256 | Impossible | Likely unroutable |