Plotting for write read time and avail logs.

plot_alsa_status.py

@@ -0,0 +1,92 @@
+#!/usr/bin/env python3
+"""Parse ALSA status log file and plot avail value over time."""
+
+import sys
+import re
+import os
+from datetime import datetime
+
+import matplotlib.pyplot as plt
+
+
+TIMESTAMP_RE = re.compile(r"^===== (\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}\.\d+) =====")
+AVAIL_RE = re.compile(r"^avail\s*:\s*(\d+)")
+
+
+def parse_log(log_path):
+    timestamps = []
+    avail_values = []
+
+    with open(log_path, "r") as f:
+        current_timestamp = None
+        for line in f:
+            line = line.strip()
+            
+            # Check for timestamp line
+            ts_match = TIMESTAMP_RE.match(line)
+            if ts_match:
+                current_timestamp = datetime.strptime(ts_match.group(1), "%Y-%m-%d %H:%M:%S.%f")
+                continue
+            
+            # Check for avail line (only if we have a timestamp)
+            if current_timestamp:
+                avail_match = AVAIL_RE.match(line)
+                if avail_match:
+                    timestamps.append(current_timestamp)
+                    avail_values.append(int(avail_match.group(1)))
+                    current_timestamp = None  # Reset until next timestamp
+
+    if not timestamps:
+        print("No valid timestamp/avail pairs found in the log file.", file=sys.stderr)
+        sys.exit(1)
+
+    # Convert to relative seconds from first timestamp
+    t0 = timestamps[0]
+    seconds = [(t - t0).total_seconds() for t in timestamps]
+    return seconds, avail_values
+
+
+def plot(seconds, avail_values, out_path):
+    plt.figure(figsize=(12, 6))
+    plt.plot(seconds, avail_values, label="avail", linewidth=1, alpha=0.7)
+    
+    # Add moving average (windowed mean)
+    if len(avail_values) >= 10:  # Only if we have enough data points
+        window_size = min(50, len(avail_values) // 10)  # Adaptive window size
+        import numpy as np
+        moving_avg = np.convolve(avail_values, np.ones(window_size)/window_size, mode='valid')
+        # Adjust timestamps for the moving average (they align with window centers)
+        ma_seconds = seconds[window_size-1:]
+        plt.plot(ma_seconds, moving_avg, label=f"moving mean (window={window_size})", linewidth=2)
+    
+    plt.xlabel("Time (s)")
+    plt.ylabel("Available samples")
+    plt.title("ALSA Available Samples Over Time")
+    plt.legend()
+    plt.grid(True)
+    plt.tight_layout()
+    plt.savefig(out_path, dpi=150)
+    print(f"Plot saved to {out_path}")
+
+
+def main():
+    if len(sys.argv) != 2:
+        print(f"Usage: {sys.argv[0]} <path_to_alsa_status_log>", file=sys.stderr)
+        sys.exit(1)
+
+    log_path = sys.argv[1]
+    if not os.path.isfile(log_path):
+        print(f"File not found: {log_path}", file=sys.stderr)
+        sys.exit(1)
+
+    seconds, avail_values = parse_log(log_path)
+
+    log_dir = os.path.dirname(os.path.abspath(log_path))
+    log_base = os.path.splitext(os.path.basename(log_path))[0]
+    out_path = os.path.join(log_dir, f"{log_base}_avail_plot.png")
+
+    plot(seconds, avail_values, out_path)
+
+
+if __name__ == "__main__":
+    main()