一，工具简介
dbstat用于追踪由MySQL或PostgreSQL数据库进程执行的查询，并显示查询延迟的直方图。
二，代码示例
#!/usr/bin/env python
from bcc import BPF, USDT
import argparse
import subprocess
from time import sleep, strftime
examples = """
dbstat postgres # display a histogram of PostgreSQL query latencies
dbstat mysql -v # display MySQL latencies and print the BPF program
dbstat mysql -u # display query latencies in microseconds (default: ms)
dbstat mysql -m 5 # trace only queries slower than 5ms
dbstat mysql -p 408 # trace queries in a specific process
"""
parser = argparse.ArgumentParser(
description="",
formatter_class=argparse.RawDescriptionHelpFormatter,
epilog=examples)
parser.add_argument("-v", "--verbose", action="store_true",
help="print the BPF program")
parser.add_argument("db", choices=["mysql", &