Files/ComputerAssignments/CA2/trace_analyzer.py

from perfetto.trace_processor import TraceProcessor

def analyze_trace(trace_path):
    print(f"Loading trace: {trace_path}")
    # Load the trace using the python API
    tp = TraceProcessor(trace=trace_path)
    
    print("\n--- Q1 & Q6: Sensor Call Count & Average Duration ---")
    q1_it = tp.query('SELECT count(1) as cnt, avg(dur) as avg_dur_ns, max(dur) as max_dur_ns FROM slice WHERE name LIKE "%onSensorChanged%"')
    for row in q1_it:
        cnt = row.cnt
        avg_dur_ms = row.avg_dur_ns / 1e6 if row.avg_dur_ns else 0
        max_dur_ms = row.max_dur_ns / 1e6 if row.max_dur_ns else 0
        print(f"Total onSensorChanged calls: {cnt}")
        print(f"Average Duration: {avg_dur_ms:.4f} ms")
        print(f"Max Duration: {max_dur_ms:.4f} ms")

    print("\n--- Q3: Actual Sampling Period ---")
    q3_it = tp.query('''
        SELECT avg(diff) as avg_diff_ns 
        FROM (
            SELECT ts - lag(ts) OVER (ORDER BY ts) as diff 
            FROM slice 
            WHERE name LIKE "%onSensorChanged%"
        ) WHERE diff IS NOT NULL
    ''')
    for row in q3_it:
        avg_diff_ms = row.avg_diff_ns / 1e6 if row.avg_diff_ns else 0
        print(f"Average time between sensor readings: {avg_diff_ms:.4f} ms")

    print("\n--- Q4 & Q10: Thread Statistics for com.airmouse ---")
    q4_it = tp.query('''
        SELECT thread.name, sum(thread_state.dur) as total_dur_ns, thread_state.state 
        FROM thread_state 
        JOIN thread USING(utid) 
        JOIN process USING(upid)
        WHERE process.name = 'com.airmouse'
        GROUP BY thread.name, thread_state.state
        ORDER BY total_dur_ns DESC
        LIMIT 10
    ''')
    for row in q4_it:
        dur_ms = row.total_dur_ns / 1e6 if row.total_dur_ns else 0
        print(f"Thread: {row.name}, State: {row.state}, Total Time: {dur_ms:.2f} ms")

if __name__ == "__main__":
    analyze_trace('trace_file.perfetto-trace')