CPU Usage During Simulation
Simulation Computation Threads
Time-series data is computed on a single thread (using only one CPU core at a time); other data can be computed in parallel.
Geometry Removal
Geometry removal is single-threaded because sequential cutting is required to obtain the correct CWE (Cutter-Workpiece Engagement). The workpiece geometry surface after removal appears in light pink, which typically indicates that the physics for that region have not yet been computed.
Physics Computation
Cutting force computation begins after CWE is obtained. Since it is independent of computation order, it runs in multi-threaded mode under normal conditions. Torque and other physical quantities are also computed in parallel during this stage.
Temperature computation must follow time-series order, so it converges back to a single thread.
The entire machining simulation alternates between these modes. Once a step is fully computed, it is colored according to the designated indicator.
CPU Usage
High Geometry Resolution
When geometry resolution is high, geometry removal is faster than physics computation, so a large area of light pink follows behind the tool during simulation. There is a cap on the number of unfinished steps; geometry removal only proceeds when the count is within that limit. When physics computation cannot keep up with geometry removal, the number of pink steps stays constant.
In this scenario, the workload is primarily multi-core (physics computation), and you are more likely to see high multi-core CPU utilization.

Low Geometry Resolution
When geometry resolution is low, geometry removal is slower than physics computation, so the light pink area is barely visible.
In this scenario, the workload is primarily single-core (geometry computation).

Balanced State
If the geometry resolution is such that geometry and physics computation do not bottleneck each other, the light pink area appears and fluctuates within a certain range. In this case, physics computation does not hold back geometry computation, and geometry computation is typically the performance bottleneck.
CPU Not Fully Utilized
Possible reasons why the CPU is not fully utilized include:
- The operating system reserves headroom to ensure the GUI remains responsive. For example, Windows desktop applications (such as WPF) lower the priority of non-GUI threads by one level.
- The software/hardware throughput has reached its limit for the process. The reported CPU usage may not reach 100%, but other resources such as cache and bus bandwidth may be saturated. System-level factors like branch misprediction are also not reflected in the reported CPU usage.
There is currently no solution for this.