From 29ea7b229ef365a0a0f39a196f62deed47ca624b Mon Sep 17 00:00:00 2001
From: Sam Hadow <sam.hadow@inbox.lv>
Date: Mon, 24 Mar 2025 16:59:32 +0100
Subject: [PATCH] parallelize runs

---
 src/main.py | 115 +++++++++++++++++++++++++++++-----------------------
 1 file changed, 64 insertions(+), 51 deletions(-)

diff --git a/src/main.py b/src/main.py
index 68767a6..8bab16d 100644
--- a/src/main.py
+++ b/src/main.py
@@ -1,9 +1,12 @@
 #!/bin/python3
 import random
+import os
+import time
 from heapq import heappush, heappop
 import matplotlib.pyplot as plt
 from scipy.stats import t
 import numpy as np
+from multiprocessing import Pool
 
 class Event:
     def __init__(self, event_type, request):
@@ -131,10 +134,26 @@ class Simulation:
 
 
 
+def run_single_simulation(args):
+    c, lambda_val, simulation_time = args
+    # for different seed in each process
+    random.seed(time.time() + os.getpid())
+    try:
+        sim = Simulation(c, lambda_val)
+        sim.run(simulation_time)
+        if len(sim.response_times) > 0:
+            run_mean = sum(sim.response_times) / len(sim.response_times)
+            loss_rate = sim.loss_rate
+            return (run_mean, loss_rate)
+        else:
+            return None
+    except ValueError:  # Loss rate too high
+        return None
+
 def simulation_wrapper():
     C_values = [1, 2, 3, 6]
     simulation_time = 1000
-    num_runs = 10
+    num_runs = 12
     min_runs = 5
     confidence_level = 0.95
 
@@ -142,62 +161,55 @@ def simulation_wrapper():
 
     plt.figure(figsize=(12, 8))
 
-    for c in C_values:
-        lambda_points = []
-        means = []
-        ci_lower = []
-        ci_upper = []
-        print(f"\nProcessing C={c}")
+    with Pool() as pool: # pool of workers
+        for c in C_values:
+            lambda_points = []
+            means = []
+            ci_lower = []
+            ci_upper = []
+            print(f"\nProcessing C={c}")
 
-        for lambda_val in lambda_vals:
-            run_results = []
-            loss_rates = []
+            for lambda_val in lambda_vals:
+                # run num_runs simulation for each lambda
+                args_list = [(c, lambda_val, simulation_time) for _ in range(num_runs)]
+                results = pool.map(run_single_simulation, args_list)
 
-            # run num_runs simulation for each lambda
-            for _ in range(num_runs):
-                try:
-                    sim = Simulation(c, lambda_val)
-                    sim.run(simulation_time)
+                # collect results from successful simulations
+                successful_results = [res for res in results if res is not None]
+                run_results = [res[0] for res in successful_results]
+                loss_rates = [res[1] for res in successful_results]
 
-                    if len(sim.response_times) > 0:
-                        run_mean = sum(sim.response_times)/len(sim.response_times)
-                        run_results.append(run_mean)
-                        loss_rates.append(sim.loss_rate)
+                # reject if not enough successful run
+                if len(run_results) >= min_runs:
+                    # statistics
+                    mean_rt = np.mean(run_results)
+                    std_dev = np.std(run_results, ddof=1)
+                    n = len(run_results)
 
-                except ValueError: # lossrate too high
+                    # confidence interval
+                    t_value = t.ppf((1 + confidence_level)/2, n-1)
+                    ci = t_value * std_dev / np.sqrt(n)
+
+                    # loss rate
+                    mean_loss = np.mean(loss_rates)
+
+                    # store results
+                    lambda_points.append(lambda_val)
+                    means.append(mean_rt)
+                    ci_lower.append(mean_rt - ci)
+                    ci_upper.append(mean_rt + ci)
+
+                    print(f"C={c}, λ={lambda_val:.2f}, Mean RT={mean_rt:.2f} ± {ci:.2f}, Loss Rate={mean_loss:.2%}")
+                elif len(run_results) > 0:
+                    print(f"λ={lambda_val:.2f} skipped - only {len(run_results)} successful run(s)")
                     continue
-
-            # reject if not enough successful run
-            if len(run_results) >= min_runs:
-                # statistics
-                mean_rt = np.mean(run_results)
-                std_dev = np.std(run_results, ddof=1)
-                n = len(run_results)
-
-                # confidence interval
-                t_value = t.ppf((1 + confidence_level)/2, n-1)
-                ci = t_value * std_dev / np.sqrt(n)
-
-                # loss rate
-                mean_loss = np.mean(loss_rates)
-
-                # store results
-                lambda_points.append(lambda_val)
-                means.append(mean_rt)
-                ci_lower.append(mean_rt - ci)
-                ci_upper.append(mean_rt + ci)
-
-                print(f"C={c}, λ={lambda_val:.2f}, Mean RT={mean_rt:.2f} ± {ci:.2f}, Loss Rate={mean_loss:.2%}")
-            elif len(run_results) > 0:
-                print(f"λ={lambda_val:.2f} skipped - only {len(run_results)} successful run(s)")
-                continue
-            else:
-                print(f"Stopped at λ={lambda_val:.2f} - no successful run")
-                break
+                else:
+                    print(f"Stopped at λ={lambda_val:.2f} - no successful run")
+                    break
 
 
-        plt.plot(lambda_points, means, label=f'C={c}')
-        plt.fill_between(lambda_points, ci_lower, ci_upper, alpha=0.2)
+            plt.plot(lambda_points, means, label=f'C={c}')
+            plt.fill_between(lambda_points, ci_lower, ci_upper, alpha=0.2)
 
     plt.xlabel('Arrival Rate (λ)')
     plt.ylabel('Mean Response Time')
@@ -207,5 +219,6 @@ def simulation_wrapper():
     plt.show()
 
 
-
+if __name__ == '__main__':
+    simulation_wrapper()