Plotting for write read time and avail logs.

plot_perf_log.py

@@ -0,0 +1,81 @@
+#!/usr/bin/env python3
+"""Parse Perf lines from a log file and plot sample mean, write mean, and loop mean over time."""
+
+import sys
+import re
+import os
+from datetime import datetime
+
+import matplotlib.pyplot as plt
+
+
+PERF_RE = re.compile(
+    r"^(\w+ \d+ \d+:\d+:\d+) .* Perf\(.*?\):"
+    r".*?sample mean=([\d.]+)ms"
+    r".*?write mean=([\d.]+)ms"
+    r".*?loop mean=([\d.]+)ms"
+)
+
+
+def parse_log(log_path):
+    timestamps = []
+    sample_means = []
+    write_means = []
+    loop_means = []
+
+    with open(log_path, "r") as f:
+        for line in f:
+            m = PERF_RE.search(line)
+            if m:
+                ts_str, sample, write, loop = m.groups()
+                ts = datetime.strptime(ts_str, "%b %d %H:%M:%S")
+                timestamps.append(ts)
+                sample_means.append(float(sample))
+                write_means.append(float(write))
+                loop_means.append(float(loop))
+
+    if not timestamps:
+        print("No Perf lines found in the log file.", file=sys.stderr)
+        sys.exit(1)
+
+    t0 = timestamps[0]
+    seconds = [(t - t0).total_seconds() for t in timestamps]
+    return seconds, sample_means, write_means, loop_means
+
+
+def plot(seconds, sample_means, write_means, loop_means, out_path):
+    plt.figure(figsize=(12, 6))
+    plt.plot(seconds, sample_means, label="sample mean (ms)")
+    plt.plot(seconds, write_means, label="write mean (ms)")
+    plt.plot(seconds, loop_means, label="loop mean (ms)")
+    plt.xlabel("Time (s)")
+    plt.ylabel("Duration (ms)")
+    plt.title("Perf Metrics 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_log_file>", 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, sample_means, write_means, loop_means = 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}_perf_plot.png")
+
+    plot(seconds, sample_means, write_means, loop_means, out_path)
+
+
+if __name__ == "__main__":
+    main()