统计各实例流量分布

def solve():
    from pyodide.http import open_url
    from io import StringIO
    import pandas as pd
    traffic_csv = open_url("https://data.zuihe.com/dbd/ms-iot/state_04/traffic_log.csv").read()
    traffic = pd.read_csv(StringIO(traffic_csv))
    print("流量分布统计:")
    total = len(traffic)
    for svc, grp in traffic.groupby('service'):
        print(f"  {svc}: {len(grp)}次")
        for inst, ig in grp.groupby('instance_id'):
            pct = len(ig)/total
            avg_lat = ig['latency_ms'].mean()
            print(f"    {inst}: {len(ig)}次 ({pct:.1%}), avg_latency={avg_lat:.1f}ms")