OpenSSL 3.0 performance issue: SSLContext.set_default_verify_paths / load_verify_locations about 5x slower

Bug report
Example code in ubuntu20.04(openssl1.1) is much faster than ubuntu22.04(openssl3.x)
Not just speed, CPU occupancy ubuntu22.04(openssl3.x) is many times of ubuntu20.04(openssl1.1)
I'm not sure whether it's OpenSSL or Python adaptation problem

import socket
import ssl
import time

import certifi
hostname = 'www.python.org'  # any support https hostname
times = 100
pem_where = certifi.where()
context = ssl.create_default_context()
verify_total_time = 0

for i in range(times):
    with socket.create_connection((hostname, 443)) as sock:
        with context.wrap_socket(sock, server_hostname=hostname) as ssock:
            verify_start_time = time.time()
            context.load_verify_locations(pem_where)
            verify_total_time += time.time() - verify_start_time
            ssock.version()
            
print(f"total {verify_total_time:.4f}, avg {verify_total_time/times:.4f}")

in my environment with docker:

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
 3321 root      20   0  304140  81148  12792 S  42.0   0.8   0:29.69 ipython    (ubuntu22.04)
 3850 root      20   0  203348  52632  11576 S  16.7   0.5   0:06.34 ipython    (ubuntu20.04)

total 5.8634, avg 0.0586  (ubuntu22.04)
total 0.6753, avg 0.0068  (ubuntu20.04)

Your environment

• CPython versions tested on: 3.10.5
• Operating system and architecture: ubuntu20.04(openssl1.1) and ubuntu22.04(openssl3.0.2), build from source
• certifi==2022.6.15

从提供的 Python 复现程序开始，在 Ubuntu 20.04/OpenSSL 1.1 和 Ubuntu 22.04/OpenSSL 3.0.2 上对 SSLContext.load_verify_locations 和 set_default_verify_paths 进行基准测试。追踪回归问题究竟出在 CPython 的 ssl 集成中还是 OpenSSL 中，然后确认原因，并根据报告中的耗时验证性能改进。