docs: update index.md — PI not PID, accurate Monitor/Actuator, platforms, no emojis

Made-with: Cursor

Author: GaetanoCarlucci

docs/index.md

@@ -5,11 +5,11 @@ title: CPU Load Generator
 
 # CPU Load Generator Project
 
-Welcome to the CPU Load Generator project — a Python-based tool that generates a fixed CPU load for a finite period using a PID regulator.
+Welcome to the CPU Load Generator project — a Python-based tool that generates a fixed CPU load for a finite or indefinite period on one or more CPU cores, using a **PI controller** (proportional–integral).
 
-![PID Regulator Block Diagram](https://gaetanocarlucci.altervista.org/wp-content/uploads/2024/07/pid-1.png)
+![PI Regulator Block Diagram](https://gaetanocarlucci.altervista.org/wp-content/uploads/2024/07/pid-1.png)
 
-## 💡 Motivation
+## Motivation
 
 This project is ideal for:
 
@@ -19,28 +19,33 @@ This project is ideal for:
 - **Education & Training**  
 - **Thermal & Power Analysis**
 
-## 🧠 Architecture
+## Architecture
 
 The system consists of:
 
 - **CPU Target Load**
 - **Monitor Thread** for actual CPU usage measurement
-- **Controller Thread** (PID regulator)
+- **Controller Thread** (PI regulator)
 - **Actuator** adjusting sleep time for control
 - **Disturbances** (e.g., other processes)
 
-## 🧪 Monitor Thread
+## Monitor Thread
 
-Uses `psutil` to sample CPU load:
+Uses `psutil` to sample the **current process** CPU usage (per core when affinity is set):
 ```python
-psutil.cpu_percent(interval)
+p = psutil.Process(os.getpid())
+sample = p.cpu_percent(sampling_interval)
 ```
 
-This blocks the thread for the sampling interval, ensuring timing consistency.
+The call blocks for the sampling interval, ensuring timing consistency.
 
-## 🔧 Controller Thread (PID Regulator)
+## Controller Thread (PI Regulator)
 
-Calculates a control signal to modulate load. If error is positive (load too low), it **reduces sleep** to increase load, and vice versa.
+Calculates a control signal (sleep time) to modulate load. If the error is positive (load too low), it **reduces sleep** to increase load, and vice versa. Tuned experimentally with `kp` and `ki`.
+
+## Actuator
+
+The actuator applies the controller output by alternating CPU-bound work and sleep. Less sleep ⇒ higher load.
 
 ```python
 def generate_load(self, sleep_time):
@@ -52,15 +57,15 @@ def generate_load(self, sleep_time):
     time.sleep(sleep_time)
 ```
 
-Tuned experimentally with `kp` and `ki`.
-
-## 📊 Results
+## Results
 
 The figure below shows the controller maintaining 50% CPU load.
 
 ![50% Target CPU Load](https://gaetanocarlucci.altervista.org/wp-content/uploads/2024/07/50-Target-Load.png)
 
-## 📎 Resources
+**Supported platforms:** Linux, macOS, and Windows (see [README](https://github.com/GaetanoCarlucci/CPULoadGenerator#readme) for setup). Use `--plot` to show the load curve and save a PNG.
+
+## Resources
 
 - [Source Code on GitHub](https://github.com/GaetanoCarlucci/CPULoadGenerator)
 - [Original Article](https://gaetanocarlucci.altervista.org/cpu-load-generator-project/)