问使用Nginx作为Sanic + Gunicorn反向代理时性能下降

EN

OS: Ubuntu 18.04    
Python version: 3.7.2    
Sanic version: 18.12.0    
Processor: i3-4130

wrk -t8 -c1000 -d60s --timeout 2s http://127.0.0.1:8080/
Running 1m test @ http://127.0.0.1:8080/
  8 threads and 1000 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency    29.54ms   15.13ms 175.77ms   71.23%
    Req/Sec     4.32k     1.29k   19.46k    64.77%
  2060010 requests in 1.00m, 249.50MB read
Requests/sec:  34281.64
Transfer/sec:      4.15MB

wrk -t8 -c1000 -d60s --timeout 2s http://127.0.0.1:8081/
Running 1m test @ http://127.0.0.1:8081/
  8 threads and 1000 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency   364.78ms  271.20ms   1.39s    67.53%
    Req/Sec   370.88    251.66     3.52k    87.12%
  177223 requests in 1.00m, 30.42MB read
Requests/sec:   2948.79
Transfer/sec:    518.25KB

from sanic import Sanic
from sanic.response import json


app = Sanic()
app.config.ACCESS_LOG = False

@app.route("/")
async def test(request):
    return json({"hello": "world"})

gunicorn --bind 127.0.0.1:8080 --workers 8 --threads 4 app:app --worker-class sanic.worker.GunicornWorker --name SanicHelloWorld

worker_processes 8;
worker_rlimit_nofile 400000;
thread_pool sanic_thread_pool threads=32 max_queue=65536;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
    multi_accept on;
    worker_connections 25000;
    use epoll;
    accept_mutex off;
}

http {
    access_log off;
    sendfile on;
    sendfile_max_chunk 512k;
    tcp_nopush on;
    tcp_nodelay on;
    server_names_hash_bucket_size 64;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;
    proxy_set_header Host $http_host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_redirect off;

    include /etc/nginx/mime.types;
    default_type application/octet-stream;

    include /etc/nginx/conf.d/*.conf;
    include /etc/nginx/sites-enabled/*;

    upstream sanic-test {
        server 127.0.0.1:8080;
    }
}

server {
    listen 8081;
    listen [::]:8081;

    server_name sanic-test.com www.sanic-test.com;

    location / {
        aio threads=sanic_thread_pool;
        proxy_pass http://127.0.0.1:8080;
    }
}